INTERNATIONAL ATOMIC ENERGY AGENCYVIENNA

ISBN 9789201004086ISSN 00741914

This report describes the procedures for preparing kits for the formulation of 23 selected 99mTc radiopharmaceuticals. Details of the preparation of ten of the active ingredients are also included. The procedures described here can be used to develop manuals, monographs and standard operating procedures. This report is expected to serve as a guide to radiopharmaceutical manufacturing centres and centralized pharmacies involved in the production of kits. It will be a useful resource for the many hospital radiopharmacies that routinely use the kits to compound 99mTc radiopharmaceuticals, and a source of information for regulators of radiopharmaceuticals.

Technetium-99m Radiopharmaceuticals:

Manufacture of Kits

Technical Reports SeriEs No. 466

Technetium

-99m Radiopharm

aceuticals: Manufacture of Kits

technical repor

tS series no. 466

200 pages 12 mm

D466_covI-IV.indd 1 2008-08-19 10:20:00

TECHNETIUM-99mRADIOPHARMACEUTICALS:

MANUFACTURE OF KITS

The following States are Members of the International Atomic Energy Agency:

The Agencthe IAEA held atThe Headquartersenlarge the contrib

AFGHANISTANALBANIAALGERIAANGOLAARGENTINAARMENIAAUSTRALIAAUSTRIAAZERBAIJANBANGLADESHBELARUSBELGIUMBELIZEBENINBOLIVIABOSNIA AND HERBOTSWANABRAZILBULGARIABURKINA FASOCAMEROONCANADACENTRAL AFRICA REPUBLICCHADCHILECHINACOLOMBIACOSTA RICACTE DIVOIRECROATIACUBACYPRUSCZECH REPUBLICDEMOCRATIC RE OF THE CONGODENMARKDOMINICAN REPECUADOREGYPTEL SALVADORERITREAESTONIAETHIOPIAFINLANDFRANCEGABONGEORGIAGERMANYGHANA

GREECEGUATEMALAHAITIHOLY SEEHONDURASHUNGARYICELANDINDIAINDONESIAIRAN, ISLAMIC REPUBLIC OF IRAQIRELANDISRAEL

NORWAYPAKISTANPALAUPANAMAPARAGUAYPERUPHILIPPINESPOLANDPORTUGALQATARREPUBLIC OF MOLDOVAROMANIARUSSIAN FEDERATIONys Statute was approved on 23 October 1956 by the Conference on the Statute of United Nations Headquarters, New York; it entered into force on 29 July 1957. of the Agency are situated in Vienna. Its principal objective is to accelerate and ution of atomic energy to peace, health and prosperity throughout the world.

ZEGOVINA

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PUBLIC

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ITALYJAMAICAJAPANJORDANKAZAKHSTANKENYAKOREA, REPUBLIC OFKUWAITKYRGYZSTANLATVIALEBANONLIBERIALIBYAN ARAB JAMAHIRIYALIECHTENSTEINLITHUANIALUXEMBOURGMADAGASCARMALAWIMALAYSIAMALIMALTAMARSHALL ISLANDSMAURITANIAMAURITIUSMEXICOMONACOMONGOLIAMONTENEGROMOROCCOMOZAMBIQUEMYANMARNAMIBIANETHERLANDSNEW ZEALANDNICARAGUANIGERNIGERIA

SAUDI ARABIASENEGALSERBIASEYCHELLESSIERRA LEONESINGAPORESLOVAKIASLOVENIASOUTH AFRICASPAINSRI LANKASUDANSWEDENSWITZERLANDSYRIAN ARAB REPUBLICTAJIKISTANTHAILANDTHE FORMER YUGOSLAV REPUBLIC OF MACEDONIATUNISIATURKEYUGANDAUKRAINEUNITED ARAB EMIRATESUNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELANDUNITED REPUBLIC OF TANZANIAUNITED STATES OF AMERICAURUGUAYUZBEKISTANVENEZUELAVIETNAMYEMENZAMBIAZIMBABWE

RADMA

IN

TECHNICAL REPORTS SERIES No. 466TECHNETIUM-99m IOPHARMACEUTICALS: NUFACTURE OF KITS

TERNATIONAL ATOMIC ENERGY AGENCY

VIENNA, 2008

IAEA

TechnI

SII

1QuAto(In

IAE

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etium-99m radiopharmaceuticals : manufacture of kits. Vienna : nternational Atomic Energy Agency, 2008.

p. ; 24 cm. (Technical reports series, ISSN 00741914 ; no. 466)TI/DOC/010/466SBN 9789201004086ncludes bibliographical references.

. Technetium Therapeutic use. 2. Radiopharmaceuticals ality control. 3. Radiopharmaceutical industry. I. International mic Energy Agency. II. Series: Technical reports series

ternational Atomic Energy Agency); 466.

AL 0800527

tions in printed or electronic form must be obtained and is ct to royalty agreements. Proposals for non-commercial and translations are welcomed and considered on a case-by-case s should be addressed to the IAEA Publishing Section at:

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les.publications@iaea.org w.iaea.org/books

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Printed by the IAEA in AustriaAugust 2008

STI/DOC/010/466

FOREWORD

Technetium-99m radiopharmaceuticals are in widespread use owing to the availability and affordability of 99Mo/99mTc generators and the variety of kits for formulating the desired products. Together, they provide an array of specific tools for diagnosing a large number of diseases affecting the bones and major organs of the body such as the heart, brain, liver, kidney and thyroid. Nuclear medicsafe for adminsupports Memand cold kitcooperation adisseminate ureducing costshelping to mak

This pubprocedures forthe active ingrused to develoreport is expecentres and cewill be a usefuuse the kits toinformation fo

The IAEthe manuscripreviewers for responsible foand Chemical ine requires high quality radiopharmaceuticals and kits that are istration and efficacious for a given application. The IAEA

ber States in building capacity in the area of 99mTc generators s through coordinated research projects (CRPs), technical ctivities and the publication of relevant reports that help seful information. These efforts have contributed greatly to and increasing the efficiency of resource utilization, thereby e nuclear medicine cost effective in Member States. lication presents the theoretical basis of and describes the preparing 23 selected kits. Details of the preparation of ten of edients are also included. The procedures described here can be p manuals, monographs and standard operating procedures. This cted to serve as a guide to radiopharmaceutical manufacturing ntralized pharmacies involved in the production of such kits. It l resource for the many hospital radiopharmacies that routinely compound 99mTc radiopharmaceuticals, and a useful source of r regulators of radiopharmaceuticals. A thanks J. Krnyei and K. Ozker for compiling and reviewing t, the experts who provided input for the report, and the their valuable suggestions and comments. The IAEA officer r this publication was M.R.A. Pillai of the Division of Physical Sciences.

Although contained in thresponsibility fo

The use ojudgement by theof their authoriti

The mentias registered) doconstrued as an EDITORIAL NOTE

great care has been taken to maintain the accuracy of information is publication, neither the IAEA nor its Member States assume any r consequences which may arise from its use.f particular designations of countries or territories does not imply any publisher, the IAEA, as to the legal status of such countries or territories, es and institutions or of the delimitation of their boundaries.on of names of specific companies or products (whether or not indicated es not imply any intention to infringe proprietary rights, nor should it be endorsement or recommendation on the part of the IAEA.

CONTENTS

1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1. Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2. Objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51.3. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

REFERENCE

2. TECHNE

2.1. Bas2.2. Firs2.3. Sec2.4. Nov2.5. Des2.6. Pre

bio

REFERENCE

3. GOOD M

3.1. Ma3.2. Qu3.3. Per3.4. Pre3.5. Do3.6. Pro3.7. Qu3.8. Sta3.9. Con3.10. Com3.11. Self3.12. Rel

BIBLIOGRAS TO SECTION 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

TIUM CHEMISTRY: THE STATE OF THE ART . . . . . 7

ic chemical properties of technetium . . . . . . . . . . . . . . . . . . 7t generation technetium radiopharmaceuticals . . . . . . . . . . 7ond generation technetium radiopharmaceuticals . . . . . . . 11el technetium chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14igned molecules and bioconjugates . . . . . . . . . . . . . . . . . . . 19cursors and chelating agents needed for the labelling of molecules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

S TO SECTION 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

ANUFACTURING PRACTICE . . . . . . . . . . . . . . . . . . . . 26

in components of GMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26ality management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27sonnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27mises and equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28cumentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36duction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37ality control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39bility testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40tract manufacture and analysis . . . . . . . . . . . . . . . . . . . . . . . 42plaints and product recalls . . . . . . . . . . . . . . . . . . . . . . . . . . 42

-inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42ationship between GMP and ISO regulation . . . . . . . . . . . . 43

PHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

4. GENERAL PROCEDURES FOR PRODUCTION OF KITS . . . 44

4.1. Batch planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454.2. Washing and sterilization of glassware and stoppers . . . . . . . . 454.3. Starting materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464.4. Preparation of bulk solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464.5. Sterile filtration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474.6. Dis4.7. Cri4.8. Sum4.9. Qu4.10. Pac4.11. Lea

BIBLIOGRA

5. GENER

5.1. Qu5.2. Qu5.3. Qu

BIBLIOGRA

6. QUALIT

6.1. Cle6.2. Fre6.3. Pac6.4. Wa6.5. Nit6.6. Com6.7. Oth

REFERENCEBIBLIOGRA

7. PRODUFOR KIT

7.1. Prepensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47mping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

mary of in-process controls . . . . . . . . . . . . . . . . . . . . . . . . . . 48arantine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49kaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49ving the production premises . . . . . . . . . . . . . . . . . . . . . . . . . 49

PHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

AL PROCEDURES IN QUALITY CONTROL . . . . . . . . 50

ality control of starting materials . . . . . . . . . . . . . . . . . . . . . . 50ality control of active substances used in the kit . . . . . . . . . . 51ality control of finished kits . . . . . . . . . . . . . . . . . . . . . . . . . . 54

PHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Y SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

an rooms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59eze-drying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59king materials: Vials, stoppers and caps . . . . . . . . . . . . . . . . 60ter for injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60rogen gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

monly used chemicals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62er excipients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

S TO SECTION 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63PHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

CTION METHODS AND SPECIFICATIONS S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

paration of kit for 99mTc-MDP . . . . . . . . . . . . . . . . . . . . . . . . 66

7.2. Preparation of kit for 99mTc-HMDP . . . . . . . . . . . . . . . . . . . . . . 697.3. Preparation of kit for 99mTc-pyrophosphate . . . . . . . . . . . . . . . . 727.4. Preparation of kit for 99mTc-DTPA . . . . . . . . . . . . . . . . . . . . . . . 747.5. Preparation of kit for 99mTc-glucoheptonate . . . . . . . . . . . . . . . 777.6. Preparation of kit for 99mTc-MAG3 . . . . . . . . . . . . . . . . . . . . . . . 797.7. Preparation of kit for 99mTc-EC . . . . . . . . . . . . . . . . . . . . . . . . . . 837.8. Preparation of kit for 99mTc-DMSA(III) . . . . . . . . . . . . . . . . . . 867.9. Pre7.10. Pre7.11. Pre7.12. Pre7.13. Pre7.14. Pre7.15. Pre7.16. Pre

nan7.17. Pre

coll7.18. Pre7.19. Pre7.20. Pre7.21. Pre7.22. Pre7.23. Pre

8. SYNTHE

8.1. Syn8.2. Syn8.3. Syn8.4. Syn8.5. Syn8.6. Syn8.7. Syn8.8. Syn8.9. Syn

(alt8.10. Syn

BIBLIOGRAparation of kit for 99mTc-DMSA(V) . . . . . . . . . . . . . . . . . . . 89paration of kit for 99mTc-mebrofenin (bromo-HIDA) . . . . 91paration of kit for 99mTc-EHIDA . . . . . . . . . . . . . . . . . . . . . . 93paration of kit for 99mTc-phytate . . . . . . . . . . . . . . . . . . . . . . 96paration of kit for 99mTc-sulphur colloid . . . . . . . . . . . . . . . . 98paration of kit for 99mTc-tin colloid . . . . . . . . . . . . . . . . . . . . 102paration of kit for 99mTc-rhenium-sulphide colloid . . . . . . . 104paration of kit for 99mTchuman serum albumin (HSA) ocolloid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108paration of kit for 99mTchuman serum albumin (HSA) oid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111paration of kit for 99mTc-microspheres . . . . . . . . . . . . . . . . . 113paration of 99mTchuman immunoglobulin . . . . . . . . . . . . . 117paration of kit for 99mTc-ECD . . . . . . . . . . . . . . . . . . . . . . . . 120paration of kit for 99mTc-d,l-HMPAO . . . . . . . . . . . . . . . . . . 123paration of kit for 99mTc-MIBI . . . . . . . . . . . . . . . . . . . . . . . 126paration of kit for 99mTc-tetrofosmin . . . . . . . . . . . . . . . . . . . 129

SIS OF ACTIVE INGREDIENTS . . . . . . . . . . . . . . . . . . . 132

thesis of HMDP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132thesis of bromo-HIDA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134thesis of EHIDA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135thesis of Bz-MAG3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136thesis of L,L-EC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138thesis of L,L-ECD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139thesis of d,l-HMPAO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140thesis of Cu(I)-MIBI tetrafluoroborate . . . . . . . . . . . . . . . . 143thesis of Cu(I)-MIBI tetrafluoroborate ernate procedure) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145thesis of tetrofosmin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

PHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

ANNEX I: SAMPLE BATCH PROCESSING RECORD . . . . . . . . 153ANNEX II: SAMPLE QUALITY CONTROL CERTIFICATE . . . 161ANNEX III: LABELLING OF PAPER BOXES AND VIALS . . . . . 162ANNEX IV: SAMPLE PACKAGE INSERT . . . . . . . . . . . . . . . . . . . . . 163ANNEX V: DETERMINATION OF STANNOUS CONTENT . . . . 168ANNEX VI: RESIDUAL MOISTURE DETERMINATION

IN FREEZE-DRIED KITS . . . . . . . . . . . . . . . . . . . . . . . . . 170ANNEX VII:ANNEX VIII:ANNEX IX:

ANNEX X :

CONTRIBUTSTERILITY TESTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173ENVIRONMENTAL MONITORING . . . . . . . . . . . . . . . 179PYROGEN TEST AND BACTERIAL ENDOTOXIN TEST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184BIODISTRIBUTION STUDIES . . . . . . . . . . . . . . . . . . . . 186

ORS TO DRAFTING AND REVIEW . . . . . . . . . . . . . . . 189

1. INTRODUCTION

1.1. BACKGROUND

1.1.1. Technetium-99m radiopharmaceuticals

The grow99mTc radiophdiagnostic procwith 99mTc radiabout 15% perthe 99Mo/99mTc67 h), is a majoradionuclide, 9

nuclear reactothat collectiveglobal demandmeet the expec

Technetiuprocedures, fr99mTc-octreotidmultiple oxidaproduce a varimajor advantahundreds of 99

thirty are usedResearch

the 99Mo/99mTcearly 1960s [1.ceuticals has bfrom the increyear.1

Technetiuor third genera

1 A searchtions on the dev1

th of nuclear medicine has been due mainly to the availability of armaceuticals; this single isotope is used in over 80% of all edures. Each year, roughly 25 million procedures are carried out opharmaceuticals, and this figure is projected to grow at a rate of annum. The availability of short lived 99mTc (half-life: 6 h) from generator, as the daughter product of long lived 99Mo (half-life: r factor behind the universal use of this radioisotope. The parent

9Mo, is prepared in abundant quantities by the fission of 235U in a r, with a fission yield of 6%. There are several major producers ly have the capacity to produce enough 99Mo to meet current . It is also possible to enhance the capacity of 99Mo production to ted increased demand. m-99m radiopharmaceuticals are used in several diagnostic

om the use of pertechnetate for thyroid uptake to the use of e derivatives for imaging neuroendocrine tumours. Owing to its

tion states, 99mTc has a versatile chemistry, making it possible to ety of complexes with specific desired characteristics, which is a ge of 99mTc for radiopharmaceutical development. There are mTc complexes useful for diagnostic procedures, of which over in clinical studies. on 99mTc radiopharmaceuticals began after the development of generator at the Brookhaven National Laboratory, USA, in the 1]. The search for new and more efficacious 99mTc radiopharma-een a continuous process for nearly half a century, as can be seen asing number of scientific papers published on this topic every

m-99m radiopharmaceuticals can be categorized as first, second tion products, depending on their level of complexity.

of the Pubmed web site (www.pubmed.gov) shows over 40 000 publica-elopment and/or use of 99mTc radiopharmaceuticals.

21.1.1.1. First generation 99mTc radiopharmaceuticals

The first generation of technetium radiopharmaceuticals was developed mainly by taking advantage of the simple absorption, distribution, metabolism and excretion properties of the common complexes of 99mTc. These studies led to 99mTc radiopharmaceuticals for the thyroid (99mTcO4

), liver (99mTc-colloids), bone (99mTc-phosphonates) and kidney (99mTc-DTPA) [1.2, 1.3]. The majority of the proceduuse of these ra

1.1.1.2. Secon

The abilicompounds usresonance (NMhelped reseaunderlying thecareful design imaging agentcardiac imaginfosmin (Myo(exametazime,of the above behaviour of properties, sucnovel renal ag99mTc-mebroferadiopharmace

1.1.1.3. Third

Current suitable biomoradioactivity tporters. This introducing a rof that part ofagents have rethat go beyonbifunctional chTc-tricarbonylres carried out in a typical nuclear medicine department make diopharmaceuticals.

d generation 99mTc radiopharmaceuticals

ty to determine the exact molecular structure of the coordination ing powerful modern analytical tools such as nuclear magnetic R) spectroscopy, mass spectroscopy (MS) and X ray diffraction

rchers to understand the structureactivity relationships biological behaviour of the 99mTc agents. As a consequence, of new ligands and their 99mTc complexes led to the discovery of s for perfusion in the myocardium and brain. The widely used g agents 99mTc-MIBI (sestamibi, Cardiolite) and 99mTc-tetro-view), and the brain imaging agents 99mTc-HMPAO Ceretec) and 99mTc-ECD (bicisate, Neurolite) are the result strategy in the development of 99mTc complexes. The in vivo

these radiopharmaceuticals is driven by their molecular h as size, charge and lipophilicity. These products, including the ent 99mTc-MAG3 (Mertiatide) and hepatobiliary agents such as nin, are generally referred to as second generation 99mTc uticals [1.41.6].

generation 99mTc radiopharmaceuticals

designs of imaging agents are based on the careful selection of lecules to function as effective vectors for in vivo delivery of

o more specific biological targets such as receptors and trans-strategy implies that the labelling approach employed for adionuclide into a biomolecule should not lead to any distortion the molecule responsible for its biological activity. Thus, these quired the development of sophisticated labelling approaches d the technologies previously used. The introduction of the elating agent (BFCA) concept and new chemistries such as the

, Tc-nitrido, Tc-HYNIC and mixed ligand complexes have

helped to achieve that objective. The radiopharmaceuticals 99mTc-HYNIC-EDDA-TOC, developed as an alternative to 111In-octreotide, and 99mTc-TRODAT-1 are the best examples of third generation 99mTc radiophar-maceuticals [1.71.9]. The former is useful for imaging neuroendocrine tumours, and the latter is the first, and to date the only, 99mTc compound for receptor studies in the brain.

1.1.2. Future

Applicatdynamic imagientrenched artechniques devcan be harneneurology. Somowing to their

AlthoughCT) images atomography (Sincrease. As astruction algoapproaching thduction of SPdetection chatogether with ia level of funcAll of the aboutility of 99mTc

1.1.3. Kits fo

Technetiukits prepared ligand to whicagent, buffer toand excipientsshelf life, rangroom temperaand ensures a l3

role of 99mTc radiopharmaceuticals

ions of 99mTc radiopharmaceuticals for morphological and ng of renal, liver, hepatobiliary, bone, cardiac and similar well eas are expected to increase in the future. New labelling eloped in the 1990s using, for example, HYNIC and carbonyl ssed to develop new tracers for oncology, cardiology and

e of these radiopharmaceuticals will find broad acceptance low cost and wide availability. positron emission tomography/computed tomography (PET/re inherently superior to single photon emission computed PECT) images, this improvement comes at a significant price

result of current advances in detector technologies and recon-rithms, the spatial resolution of SPECT images is rapidly at of PET images, without a decrease in sensitivity. The intro-

ECT/CT has taken this imaging modality a step closer to the racteristics of PET/CT. These improvements of SPECT/CT, mproved technetium radiopharmaceuticals, will provide as high tional and anatomical information as is attainable by PET/CT. ve developments are expected to increase the demand for and radiopharmaceuticals and their kits.

r formulation of 99mTc radiopharmaceuticals

m-99m radiopharmaceuticals are generally formulated from in authorized manufacturing facilities. A cold kit contains the h 99mTc is to be complexed, an adequate quantity of reducing adjust the pH to suit the labelling conditions, stabilizing agents

. The kits are prepared in a freeze-dried form and have a long ing from several months to years. The kits can be transported at ture; however, storage in a refrigerator at 28C is advantageous ong shelf life in most cases.

41.1.4. Comp

The comas it involves room temperatechniques suc(ITLC) or highfor estimation istration to patof radiopharmStates Pharmapharmaceuticarecommendedin an ISO 5 (c(with a buffer flow bench wisterile radioph

1.1.5. Good

The manmanufacturingare used in thaspects of the

FIG. 1.1. Lamradiopharmaceuounding of radiopharmaceuticals in hospital radiopharmacies

pounding of 99mTc radiopharmaceuticals using kits is fairly easy, the addition of 99mTcO4

eluted from a generator, generally at ture but at times with heating. The use of chromatographic h as paper chromatography, instant thin layer chromatography performance liquid chromatography (HPLC) is recommended

of the radiochemical purity of the final product, prior to admin-ients [1.10]. Guidelines for aseptic compounding and dispensing aceuticals are available in chapters 707 and 1075 of the United copeia (USP) [1.11]. According to these guidelines, radio-ls are considered to be compounded sterile products, and it is that compounding of 99mTc radiopharmaceuticals be carried out lass 100, grade A) laminar flow bench located in a clean room zone). This guideline is in force as of 2008. Two types of laminar th sliding lead shields used in radiopharmacy for compounding armaceuticals are shown in Fig. 1.1.

manufacturing practices in kit production

ufacture of radiopharmaceuticals requires that current good practices (GMPs) be employed. Ensuring that current GMPs e manufacture of radiopharmaceuticals requires that several production process be considered, addressed and verified prior

inar flow benches with sliding lead shields for compounding sterile ticals (source: Graymont Inc. and Veenstra Instruments).

to, during and after production. These include the training and qualification of personnel, use of controlled materials and procedures, availability of qualified equipment, production of products in designated clean areas, application of validated processes and analytical methods, full documentation of the process, registration of the products and release of the final product by a certified person.

1.2. OBJECT

In 1992, tradiopharmaceof the first ge99mTc radiophaclinical use, somPharmacopoeiradiopharmaceproduction mmanufacturingchanges, with rbecoming man10 active ingrecontributors tothe regulatory

1.3. SCOPE

This repoof kits for formexperience offacilities and ireference for k

Issues sugeneral procedfications of gesections. Produof this book. Iactive ingrediethe chemical cdetails, freeze-5

IVE

he IAEA published a report on the preparation of kits for 99mTc uticals [1.12] that gave technical inputs for the preparation of 13 neration 99mTc radiopharmaceuticals. Since that time, several rmaceuticals not described in the report have come into routine

e of which are already described in the USP and the European a (EP). On the basis of a review of all currently used 99mTc uticals, it was decided to expand the report to include the

ethods of the most widely used kits. The requirements for the radiopharmaceuticals have also undergone significant egulations becoming more stringent and compliance with them datory. The current report provides details of 23 kits and dients. The GMPs described here are those followed by the this report and served as the basis for obtaining licences from authorities.

rt provides information on the various aspects of the production ulating 99mTc radiopharmaceuticals. It draws on the collective

experts in the installation and operation of kit production s expected to serve as guidance for kit manufacturers and as a it users.ch as principles of kit manufacture, GMP in kit production, ures for production and quality control of kits, and quality speci-nerally used equipment and materials are detailed in the initial ct specific information on selected kits is provided in Section 7

nformation is given on the production of kits, starting with the nts, and details are provided concerning the reagents required, omposition of the kits, manufacturing formulas, manufacturing drying conditions, storage and stability of the products, methods

6for radiolabelling, features of the labelled products, quality requirements and recommended quality control tests of the labelled products. Whereas the majority of the active ingredients used for the production of the kits are available from commercial manufacturers, the active ingredients of the new products are not widely available. Details on the synthesis of active ingredients are included in Section 8. The 11 annexes to the report provide useful information on general procedures for the manufacture and quality control of kits.

[1.1] RICHARisotopes Symp., R

[1.2] SRIVASTRadiotraBoca Rat

[1.3] SCHWOsynthesis,2258226

[1.4] DEUTSCtechnetiuS.J., Ed.),

[1.5] NUNN, Ationship improved

[1.6] BANERJin diagno

[1.7] RICCABCancer B

[1.8] GABRIETOC wiexpressin

[1.9] KUNG, dopamine

[1.10] ZOLLE, Control i

[1.11] UNITEDmacopeia

[1.12] INTERN99mTc RaREFERENCES TO SECTION 1

DS, P., A survey of the production at Brookhaven National Lab of the for medical research, Trans. 5th Nucl. Cong., 7th Int. Electr. Nucl. ome (1960).AVA, S.C., RICHARDS, P., Technetium-99m labeled compounds,

cers for Medical Applications (RAYUDU, G.V.S., Ed.), CRC Press Inc., on, FL (1983) 107185.CHAU, K., Technetium radiopharmaceuticals Fundamentals, structure, and development, Angew. Chem. Int. Ed. Engl. 33 (1994) 7.H, E.A., LIBSON, K., JURISSON, S., Technetium chemistry and

m radiopharmaceuticals, Progress in Inorganic Chemistry (LIPPARD, John Wiley & Sons, New York (1983) 75139.

.D., LOBERG, M.D., CONLEY, R.A., A structure-distribution rela-approach leading to the development of 99mTc-mebrofenin: An chole-scintigraphic agent, J. Nucl. Med. 24 (1983) 423430.EE, S., PILLAI, M.R.A., RAMAMOORTHY, N., Evolution of Tc-99m stic radiopharmaceuticals, Semin. Nucl. Med. 31 (2001) 260277. ONA, G., DECRISTOFORO, C., Peptide targeted imaging of cancer, iother. Radiopharm. 18 (2003) 675687. L, M., et al., An intrapatient comparison of 99mTc-EDDA/HYNIC-

th 111In-DTPA-octreotide for diagnosis of somatostatin receptor-g tumors, J. Nucl. Med. 44 (2003) 708716. H.F., Development of Tc-99m labeled tropanes: TRODAT-1 as a transporter imaging agent, Nucl. Med. Biol. 28 (2001) 505508. I. (Ed.), Technetium-99m Pharmaceuticals: Preparation and Quality

n Nuclear Medicine, Springer, Berlin (2007). STATES PHARMACOPEIAL CONVENTION, United States Phar- 30, USP Convention, Rockville, MD (2006).ATIONAL ATOMIC ENERGY AGENCY, Preparation of Kits for diopharmaceuticals, IAEA-TECDOC-649, IAEA, Vienna (1992).

2. TECHNETIUM CHEMISTRY: THE STATE OF THE ART

2.1. BASIC CHEMICAL PROPERTIES OF TECHNETIUM

Technetium, the 43rd element in the periodic table, belongs to the group of transient metals. Owing to its electron configuration of 4d5 5s2, technetium provides severdifferent ligandOS is considerthe complexesand pi electrotypes when spi

The struccoordination n(N = 4), tetrag(N = 7) or pencharacterizatiowhole moleculcationic (Z =complexing ce

The highstabilities for tthe most stablpertechnetate after long periTc-P(III) and Tgeometry. At bound to technthat is, polynucomplexes suclow stability bipyramidal gethese complex

2.2. FIRST GRADIOP

When thproduced, it w7

al opportunities for complex formation with a large number of s, and its oxidation state (OS) can change from +1 up to +7. The

ed to be a main parameter determining the chemical nature of . Technetium can form chemical bonds consisting of both sigma ns, and the sigma bonds can be of colligative and coordinative n compensation and electron pair donation occur, respectively.ture of technetium complexes can also be characterized by the umber (N), which can vary from 4 to 7, allowing tetrahedral onal pyramidal (N = 5), octahedral (N = 6), capped octahedral tagonal bipyramidal (N = 7) geometry. The third parameter for n of technetium complexes is the electric charge (Z) of the e, which may provide an anionic (Z = 1), neutral (Z = 0) or +1) character [2.1]. A summary of the different kinds of ntre and the parameters OS, N and Z is presented in Table 2.1. variability of the complexing centres results in different

he various complexes. Pertechnetate (N = 4, OS = +7, Z = 1) is e form of technetium in aqueous media. The presence of free in the solution of a technetium compound is possible, especially ods of post-labelling storage. At lower oxidation states, the Tc-S,

c-C(II) chemical bonds are quite stable in the appropriate the same time, phosphonates, in which six oxygen atoms are etium, are of a lower stability and are liable to form oligomers, clear complexes [2.2]. The hexacoordinated N2O4 and N3O3

h as DTPA, EDTA or HIDA derivatives are also of a relatively and partially transform to heptacoordinated pentagonal ometry, which might be an alternative structure provided by

ing centres and an additional oxo-oxygen.

ENERATION TECHNETIUM HARMACEUTICALS

e first generation technetium radiopharmaceuticals were as obvious that the reduction of technetium needed to be

8ensured. As thlabelling, kit foligand with Snlabelling systemnetate (the geconditions. Thsummarized be

Among 99mTc-gluconatevidence of thcomplexes arebinding (507excretion by t

TABLE 2.1. CHARACTERIZATION OF VARIOUS TECHNETIUM COMPLEXES

N OS ZComplexing centres of Tc by:

Compound Organ/tissue specificity Sigma bond Pi bond

4 +7 1 ( = O)4 Pertechnetate Thyroid

5 +5 1 ONNS

5 +5 0 NNS

6 +1+1+3+5

+1+1+1+1

CCNP

6 +4+3

+4

111

NSNO

7 +3 0 N

7 +5 1 N

Note: N = coorde short physical half-life of technetium required on the spot rmulation had to be provided by freeze-drying the appropriate (II)-chloride as a reducing agent. This resulted in a one vial , and the kit was reconstituted simply by injecting the pertech-

nerator eluate) into the freeze-dried product under aseptic e most important first generation radiopharmaceuticals are low.

the earliest technetium radiopharmaceuticals weree and 99mTc-glucoheptonate; however, no experimental e pentacoordinated geometry has been found. Although these of a hydrophilic character, they show high plasma protein 0%). Therefore, both glomerular filtration and tubular he kidneys occur with slow pharmacokinetics [2.3], and only

4

3S

2S24

= O= O= O= O

GluconateMAG3ECDMSA(V)

Red blood cell labellingKidneyKidneySoft tissue tumours

4

2S24

= O= O N

HMPAOECDNOET

Brain, white blood cellsBrainMyocardium

6

3N3, C3N2O

2O2P24

(= O)2

MIBITricarbonylQ 12Tetrofosmin

MyocardiumVariousMyocardiumMyocardium

3O33O32O46

DTPADMSA(III)HIDA derivativesPhosphonates

KidneyKidneyHepatobiliary systemBone

6Cl Teboroxime Myocardial flow

2O4 = O EDTA, DTPAHIDA derivatives

Kidney Hepatobiliary system

ination number; OS = oxidation state; Z = electric charge.

70% of the injected activity is washed out after one day. This is the reason why 99mTc-gluconate and 99mTc-glucoheptonate are no longer used for renal studies. Owing to their low stability, they are used (i) for red blood cell labelling [2.4] and (ii) as a ligand exchange partner for labelling other molecules.

Another well known radiopharmaceutical with a hydrophilic character is99mTc-DTPA. However, only up to 10% of the 99mTc-DTPA is bound to plasma proteins, and [2.5]. The ph99mTc-gluconatwithin 2 h forapplications ofities), cerebrogastrointestinausing 99mTc-DT

In an alksuccinic acid (coordinated biin the kidneys the pH does ninjectable. Whdinated asymmtechnetium viaone -S- bridgestructure of 9

asymmetric coremains boundDMSA ligandComplete uptascintigraphy uthe functionalproportional to

All 99mTccan be charact-CH(OH)- anIndependent ooligomers, whiprior to freezescintigraphy [2normal bone ahydroxyapatite9

almost complete glomerular excretion occurs via the kidneys armacokinetics of 99mTc-DTPA is much faster than that of e, and more than 90% of the injected activity is washed out 99mTc-DTPA, compared with 12 h for 99mTc-gluconate. Other 99mTc-DTPA include blood flow studies (brain, heart, extrem-spinal fluid circulation studies, studies of transport in the l tract with labelled drinks and foods, and inhalation studies PA aerosol.

aline medium (pH8), all of the free SH groups of dimercapto-DMSA) are ready to react with technetium, forming a penta-scomplex, 99mTc-DMSA(V). This biscomplex accumulates both and in soft tissue tumours such as medullar carcinomas [2.6]. If ot exceed 9, the compound is of an appropriate stability and is en labelling of DMSA is performed in acidic media, a hexacoor-etric biscomplex is formed in which one molecule is bound to

two -S- bridges and one -O- bridge, while the other is bound via and two -O- bridges, and one SH remains free. This kind of 9mTc-DMSA(III) is complete if the pH is around 3. The mplex, when injected, is taken up by the kidneys [2.7] and owing to a ligand exchange reaction occurring between the

and the protein located in the proximal tubules of the kidney. ke of 99mTc-DMSA(III) is observed 24 h post-injection. Renal

sing 99mTc-DMSA(III) provides quantitative information about mass of each individual kidney, since the renal uptake is the functional mass.-phosphonates with ligands such as MDP, HMDP and HEDP

erized by the general formula H2O3P-X-PO3H2, where X = -CH2, d -C(OH)(CH3)- for MDP, HMDP and HEDP, respectively. f the substituents, phosphonates show a tendency to form

ch can be avoided by adding antioxidants such as ascorbic acid -drying the product. Their main field of application is bone .8, 2.9], because technetium phosphonates are taken up by

nd bone lesions by chemisorption, followed by exchange on the , the inorganic matrix of the bone. Higher uptake is observed

10

when the regional blood flow is higher owing to hydroxyapatite formation accompanied by increased osteoblastic activity. Thus 28 times the activity of technetium phosphonates can accumulate in bone lesions with increased osteoblastic activity (rupture, tumour metastases, etc.) compared with normal bone. The different substituents in the phosphonates affect the pharmacoki-netics (99mTc-HMDP is faster than the others) and the lesion to normal bone activity ratio (99mTc-HEDP gives the highest contrast). In general, it is recommended

Pyrophoslyophilizate, Ssaline; this nonpertechnetate pyrophosphate(this was the fi99m-pyrophosvitro methods.partner for lab

Derivativbeen developeliver and the hheptacoordinaelectric chargeliver, similar tgall-bladder anthe aromatic rivarious HIDAThese more liptrimethyl-bromcases of imper

When inaccumulated inparticles appeatical were thethiosulphate (dithionite (Naelevated tempmore fine partnetate. In this tin oxide/hydcolloid particlephate in the p that imaging be performed 24 h post-injection.phate is used for in vivo labelling of red blood cells. The cold n(II)-pyrophosphate, can be injected after reconstitution in -radioactive compound accumulates in the red blood cells. Free is injected into the patients 20 min post-injection of the Sn(II)-, resulting in red blood cell labelling under in vivo conditions rst example of the pretargeting technique) [2.10]. Technetium-phate can also be used to perform red blood cell labelling by in Another application of pyrophosphate is as a ligand exchange elling sensitive molecules such as HMPAO.es of (N-phenyl-carbamoylmethyl)-imino diacetic acid have d as bilirubin analogues for investigating the functioning of the epatobiliary system [2.11]. These compounds are octahedral or ted pentagonal bipyramidic biscomplexes possessing a negative . After injection, they are excreted by the hepatocytes in the o the bilirubin, followed by elimination via the bile routes, d duodenum within 4560 min. By varying the substituents on ng, the lipophilic character of the molecule can be increased and derivatives can be obtained that are mostly excreted by the liver. ophilic complexes of ligands, such as diisopropyl-IDA [2.12] and o-IDA [2.13], can be used for hepatobiliary studies even in

fect liver function.jected, 99mTc colloids with a particle size of 0.12 m are the liver by phagocytosis in the Kupffer cells [2.14]. The larger r in the spleen. The first species of this kind of radiopharmaceu- 99mTc-sulphur colloids [2.15] prepared either from sodium Na2S2O3) in an acidic medium (4.6M HCl) or from sodium

2S2O4) in a neutral medium by reducing the technetium at an erature (88100oC). The 99mTc-tin colloid [2.16] may contain icles when prepared from Sn(II)-fluoride reacting with pertech-compound, the reduced hydrolysed technetium is bound to the roxide colloidal particles. Technetium-99m-rhenium-sulphide s for liver scintigraphy can be prepared from sodium thiosul-resence of hydrochloric acid and potassium perrhenate at an

elevated temperature. Recently, the 99mTc-rhenium-sulphide colloid has been used in sentinel lymph node detection [2.17]. In addition to colloids prepared in vitro, the 99mTc-phytate colloid can be formed in situ in the blood by interacting the phytate ligand with calcium content in serum [2.18].

Technetium-99m-rhenium-sulphide colloids with a particle size of 1080 nm can also be used for bone marrow scintigraphy, lymphoscintigraphy and detection of inflammation [2.19]. In this two-step procedure, a technetium pyrophosphaterhenium sulphparticle size ca

Technetiuobtained fromat pH5.2, and 9

the heat treaTechnetium-99since the acc(i.e. embolisms

2.3. SECONDRADIOP

After theticals was estabconventional technetium. Amolecules givsynthesized antechnetium raperfusion studrenal tubular fradiopharmaceimportance.

Technetiualternative tofunction, radiosecretion of a cgeometry constubular secretiwhich loses itsnuclide (i.e. ot11

complex is prepared, followed by reaction with freeze-dried ide at 100oC for 1530 min. A 99mTc nanocolloid of similar n prepared from human serum albumin (HSA) as well.m-99m macroaggregates (particle size: 1045 m) can be

HSA when the heat treated alkaline HSA solution is neutralized 9mTc microspheres (particle size: 575 m) can be attained when ted alkaline HSA solution is completely denatured [2.20]. m macroaggregates are used for perfusion lung scintigraphy, umulation in the lung is proportional to the blood flow are cold areas, having no blood supply).

GENERATION TECHNETIUM HARMACEUTICALS

success of the first generation of technetium radiopharmaceu-lished, there was demand for radiopharmaceuticals in which the

radionuclides, such as 51Cr, 131I, 197Hg, were replaced with lthough the task was difficult, a wide range of small organic

ing neutral, lipophilic or positively charged complexes were d labelled with technetium. These efforts resulted in the

diopharmaceuticals currently used for brain and myocardial ies as well as those for the investigation and quantification of unction. Thus, as cost effective alternatives to non-technetium uticals, the second generation products are of high clinical

m-99m-MAG3 (mercaptoacetyltriglycine) was developed as an o-radioiodo-hippurate [2.21]. To evaluate complete renal pharmaceuticals with high tubular secretion are needed. Tubular ompound is facilitated enzymatically by making use of a special isting of three of the molecules oxygen atoms. The highest

on was observed in the case of para-amino-hippuric acid (90%), biological activity when any kind of non-physiological radio-her than carbon, oxygen or nitrogen isotopes) is introduced into

12

the molecule. If the amino group in the para position is replaced with a hydrogen atom, and at the same time radioiodine is introduced into the ortho position, the resulting o-radioiodo-hippurate molecule shows renal tubular excretion of about 85%. At the same time, routine clinical use of radioiodo-hippuran is limited, since 125I and 131I are not suitable for gamma camera renography and 123I is too expensive in most countries. On the other hand, it was recognized that an approximately ideal geometry of the above mentioned oxygen trio wcarbonyl groupatoms could tacomplex with cthe nitrogen te

The formacetyl-triglycinS-benzoyl grouformation of inlabelling, the Sature. Up to 90enzymatically kidneys at 5 mis washed out effective renal

Technetiufirst neutral lipbrain barrier different stereknown [2.23]. Tof the injectedaccumulation isomers in theisomers are icaptured in theto the perfusio

Labellingonly a few milabelling via regularly elutewill not be sufand a greater athe reason whrecommendedould be provided by the COOH terminal and the adjacent of a simple tripeptide like triglycine, while the three nitrogen ke part in complexation with technetium. To ensure a stable oordination number 5, a mercaptoacetyl group was attached to rminal of the triglycine, resulting in an N3S complex (MAG3).ulation of the MAG3 kit consists mainly of S-benzoyl-mercapto-e, Sn(II)-chloride and tartrate as a ligand exchange partner. The p protects the active substance from oxidation (i.e. avoiding the termolecular -S-S- bridges from the free SH groups). During -benzoyl group is eliminated by applying an elevated temper-% of the 99mTc-MAG3 binds to plasma proteins but, owing to the facilitated tubular excretion, 50% of the activity is found in the in post-injection. After 3 h, more than 90% of the injected dose via urine. This pharmacokinetics allows the evaluation of the

plasma flow (ERPF) as well.m-99m-HMPAO (hexamethylpropylene amine oxime) was the ophilic technetium compound able to pass through the blood[2.22]. Due to the asymmetric carbon atoms in the ligand, oisomers of the active substance and the labelled compound are

he brain uptake of the d and l (trans) isomers is high (up to 4% dose), while the meso (syn) isomers do not show acceptable

in the brain tissues. The concentration of the appropriate trans brain is constant from 2 to 4 min post-injection, since the trans ntracellularly transformed into hydrophilic compounds and brain cells. The brain uptake of 99mTc-HMPAO is proportional

n in the tissues. of HMPAO requires great care, since a very small amount crograms of Sn(II) is used in the kit for ligand exchange pyrophosphate. If the eluate from a generator that is not d is used for radiolabelling of HMPAO, the amount of Sn(II)

ficient to reduce the total amount of technetium (99mTc + 99gTc) mount of free pertechnetate will remain in the solution. This is

y the use of fresh eluate from a continuously used generator is for labelling HMPAO. Technetium-99m-HMPAO is of poor

stability, and hence the complex must be used within 3045 min of preparation [2.24]. Technetium-99m-HMPAO also penetrates the white blood cells (leucocytes, lymphocytes), platelets and even macrophages in vitro, and hence is used for cell labelling studies for imaging infection and inflammation.

Technetium-99m-MIBI (methoxyisobutylisonitrile), or 99mTc-sestamibi, is a lipophilic complex with a positive charge that is in frequent clinical use [2.25]. To ensure theoxidation state[Tc(-C=NR)6]+atom bound towith the lone molecules arecompounds, Madduct, [Cu(Mthe procedure boiling water f

Technetiupassive diffusiomitrochondriawashout is raththan 3% of thebound part is ealso taken up i

Cationic oxidation stateDevelopment tetrofosmin [2biscomplex, focoordinated totemperature, ais similar to tha

Technetiuneutral, lipophcore, that can through the benzymatic hydthe first and 99mTc-ECD excomparison oftracer may 13

positive charge of the complex, a technetium atom in a low (+1) is reacted with the monodentate isonitrile ligand to obtain with a hexacoordinated (octahedral) structure. Each carbon the technetium possesses a non-paired electron (overlapping pair of the adjacent nitrogen), thus the technetium-sestamibi paramagnetic. Since isonitriles are volatile, not very stable IBI is available in stabilized form as copper tetrafluoroborate IBI)4]BF4, which should be decomposed during labelling, with carried out at an elevated temperature by immersing the vial in or 10 min [2.26].m-99m-MIBI is taken up by the cells of the myocardium in n [2.27] and then appears in the cytosol and is localized in the

. The uptake is proportional to the myocardial perfusion, and the er slow (excluding considerable redistribution). At stress, more injected dose is accumulated in the myocardium, while the non-liminated via the hepatobiliary route. Technetium-99m-MIBI is n tumours and metastases, expanding its clinical application.technetium complexes can also be obtained if technetium is in an of +3, such as with compound Q12, or +5, as with tetrofosmin. of compound Q12 was stopped after patient studies, while .28, 2.29] is currently available for clinical use. In the latter ur trivalent phosphorus atoms and two oxo-oxygen atoms are technetium (+5). Tetrofosmin can be labelled at ambient

nd its uptake in the myocardium and in tumours and metastases t of 99mTc-MIBI (passive diffusion, no redistribution).m-99m-ECD (ethylene-L,L-dicysteine diethylester) is a ilic technetium complex with high stability, owing to the N2S2be used even several hours after preparation. It can easily pass loodbrain barrier and is captured in the brain cells owing to rolysis, resulting in EC-monoester-monoacid and EC-diacid in second steps, respectively. Compared with 99mTc-HMPAO, hibits different pharmacokinetics in humans, thus a direct

these two tracers cannot be made: the use of one or the other be preferable, depending on the clinical case [2.30].

14

Technetium-99m-ECD is far superior to 99mTc-HMPAO regarding stability; however, it is not suitable for white cell labelling.

Ethylene-L,L-dicysteine (EC) is the free acid derivative of ECD [2.31]. Owing to the two free COOH groups, intramolecular interaction takes place between the molecules two protons and two nitrogen atoms, resulting in two intramolecular rings in the EC. For this reason, only the SH groups of EC are able to react with technetium, unless the intramolecular rings have been broken by ensthe nitrogen atN2S2 monocomthe technetiuma triangle cons99mTc-MAG3. Tuptake and wacamera renogr

Labellingwith the EC istable enoughligand exchangthe strong alkacan be carried for several hou

The chemradiopharmace

2.4. NOVEL

Novel tecsuch as receptantibiotics wibiochemical acomplexing comolecules. At activity, since tmethods can bplay a role.uring a strong alkaline medium (>pH12). In this medium, both oms and the sulphur atoms are able to bind to technetium and a plex can be obtained. In this complex, the oxo-oxygen atom of and two oxygen atoms of a COOH group form a geometry (i.e. isting of the oxygen trio) similar to those of iodo-hippuran and hus 99mTc-EC is also a tubular renal agent showing rapid renal

shout [2.322.34], and providing high image quality for gammaaphy. of EC can be accomplished using a three-vial kit formulation,

n a strong alkaline buffer (in which the stannous ions are not ) in the first vial, the Sn(II)-tartrate as a reducing agent and e partner in the second vial, and an acidic buffer to neutralize line solution just after labelling in the third vial. The procedure out at ambient temperature, with the 99mTc-EC remaining stable rs [2.32].ical formulas of selected first and second generation technetium uticals are shown in Fig. 2.1.

TECHNETIUM CHEMISTRY

hnetium chemistry involves labelling of tissue specific molecules or ligands, metabolic agents, peptides, proteins, antibodies and th technetium such that these biomolecules retain their nd physiological activities [2.35, 2.36]. To achieve this, the re must be as far as possible from the biospecific part of the the same time, the labelled species should possess high specific heir binding sites in living tissue are limited. The following three e considered the most important in which monodentate ligands

CCC

C

C

C

N-R

N-R

N-RN-R

R-N

R-N

R= -CH2 -C

CH3

CH3

OMe

Tc

Tech

O

N

NHN

MeN

Me

Me Me

H

Me

Me

HTc

EtOOC

Tech

O

R

Techne

O

Tec

HOOC

HOOC

Techn

FIG. 2.1.15

netium-MIBI

OOH

Technetium-d,l-HMPAO

O

S

NCOOEt

S

Tc

netium-L,L-ECD

Tc

O

N N

SS

COOHHOOC

_

Technetium-L,L-EC

O

O

O OO

RO

-

R = -(CHOH)3-CH2OH

Tc

tium-gluconate

O

N

N

OO

R = -CH2COOH

O

O

R

R

O

Tc

Technetium-DTPA

O

NS

R = -CH2COOH

O

OR

-

Tc

hnetium-MAG3

Tc

O

O

S S

S

O

-3O

O

SH

HOOC

O

Technetium-(III)-DMSA

O

S

S SCOOH

COOHS

-

Tc

etium-(V)-DMSA

O

O

O

NO

O

O

O

O

R

R

NH- H2C

O

R=

-

Tc

Technetium-diethyl-HIDA

HN

N

NN

N

Chemical formulas of selected technetium radiopharmaceuticals.

16

2.4.1. Nitrid

As was inthe technetiumbetween the tcomplexing cotechnetium codithiocarbamaThe TcN struchloride are reThis technetiuligand to the din Fig. 2.2 as an

When Rmolecule showlayer of the mdynamic equilipotential technNOET was nocompounds ofexample, poten

Symmetrsuch as NOETRRP-CH2-CHcomplexes canbidentate colig

[TcO4] + SnCl2 + H2N-NH-CO-(CH2)2-CO-NH-NH2 TcN synthon

TcN synthon

N SS

1

FIG. 2.2o labelling

dicated by chemical evidence, replacing the oxo-oxygen atom in complexes with a nitrido group containing a triple bond

echnetium and the nitrogen atom results in a more compact re and much higher stability [2.37]. The first of the nitrido mpounds was NOET (technetium-nitrido-N-ethyl-N ethoxy-te), which was designed as a neutral lipophilic complex [2.38]. cture can easily be prepared if hydrazino derivatives and tin

acted with pertechnetate at ambient or an elevated temperature. m-nitrido intermediate is then transformed by the appropriate esired nitrido complex. Dithiocarbamate derivatives are shown example of this reaction route.

= -Et and R = -OEt, the resulting neutral lipophilic NOET s myocardial uptake by being intercalated in the phospholipid yocytes [2.39]. A redistribution effect is observed owing to a brium involving washout and uptake, which is unique among the etium myocardial agents [2.40]. The registration procedure of t completed. By varying R and R groups, a series of neutral

lipophilic character can be obtained, which could serve as, for tial agents for brain studies [2.41].

ic nitrido complexes can be prepared, not only with a S4 core, but also with an S2P2

(III) core when the reaction partner is

2-SH (Fig. 2.3(a)). At the same time, asymmetric nitrido be prepared by using bidentate phosphino ligands with a and (Fig. 2.3(b)).

+ 2 RR N-CS2Na S

C-NRR'Tc

S

R'RN-C

'

. Preparation of Tc-nitrido complex using the [TcN] synthon.

2.4.2. HYNI

HYNIC, functions as atechnetium [2.ligands, while diacetic acid).

N

Tc

P

R R

S

P

RR

S

R or

N

P

P

Y

X

TcN

RR

RR

R'

(a) (b)

FIG. 2.3. Var(b) asymmetric l

[Biomolecule]-N

(HO

[Biomolecul

FIG. 2.4. Tech17

C labelling

the hydrazinonicotinamide introduced by Abrams et al. [2.42], BFCA, forming a bridge between the biomolecule and the 43]. The HYNIC conjugated molecules react as monodentate the coligands may be tricine or EDDA (ethylene-diamine-

A typical HYNIC-tricine labelling is shown in Fig. 2.4.

R' = biomolecule R' = biomolecule; X = S,N; Y = O,N

ious nitrido complexes of technetium: (a) symmetric labelling and abelling.

Tc

N

-NH-NH2

TcO4-

Sn+2

N

-NH-N

HN

CH2C

O C CH2OH

CH2OH

CH2OH

O

O

HN

CH2C

O C CH2OH

CH2OH

CH2

O

H-CO-(CH2)n-NH-CO- +

-CH2)3-C-NH-CH2-COOH +

e]-NH-CO-(CH2)n-NH-CO-

Room emperature

20 min

t ,

netium-99m labelling of a biomolecule through the HYNIC substrate.

18

HYNIC -S-S- cystine balso be prepa99mTc-EDDA-Htyrosine instea(as the co-ligaEDDA-HYNImetastases exp

HYNIC phosphatidylsecell death (apoimaging infectcidine (UBI 29antagonists [2formyl-methio[2.50]. HYNICbe bound [2.51a useful tool fo

2.4.3. Tricar

The use owas first propoan aqueous mmonoxide is carbonate andtemperatures b

In the preterminal (due

+ + +C

C

H2O

COO

H2OH2O

+

75oC, 30 min

TcO4-

3CO NaBH2 Na2CHO3TcH2Olabelling ensures mild conditions, avoiding the reduction of the ridges of the biomolecules; 99mTc-somatostatin derivatives can red in this manner. The best version of these derivatives is

YNIC-TOC, in which the modified octreotide (containing d of phenylalanine in the amino acid chain (TOC)) and EDDA nd) are present in the molecule [2.44, 2.45]. Technetium-99m-C-TOC is a useful diagnostic tool for imaging tumours and ressing somatostatin receptors on their surfaces.provides a successful labelling methodology in the case of the rine specific protein Annexin V for the imaging of programmed ptosis). HYNIC also allows the labelling of various agents for

ion and inflammation, such as the antimicrobial peptide ubiqui--41) [2.46], interleukin-8 [2.47], leukotriene B4 (LTB-4) receptor .48], the RP-463 chemotactic peptide-containing sequence of nyl-leucyl-phenylalanyl-lysine-HYNIC [2.49] and liposomes coupled lysine is a simple amino acid to which technetium may ], and HYNIC coupled antisense DNA [2.52] can be considered r the application of technetium in biomedical research.

bonyl labelling

f organometallic carbonyl compounds in technetium chemistry sed in 1993, and such compounds were first fully synthesized in edium in 1998 [2.53]. It was observed that, when carbon

flushed in an alkaline medium in the presence of sodium sodium borohydride, pertechnetate can be reduced at elevated y forming a transient cationic complex (Fig. 2.5).sence of a desired biomolecule containing an imidazol ring at its

to the attached histamine or histidine) as a chelating agent, the

O

FIG. 2.5. Synthesis of a Tc-tricarbonyl synthon.

transient catiotechnetium com

Initially, flushed with casodium tetrabavailable for ediary) compleximmersing it inintermediary histidine termconditions for statin derivatipeptides [2.56]

2.5. DESIGN

High biothe novel radiocan help in dligand or antigcomputer aidcomputing systand manipulatanalysis of the part of the m

CX

C

O

O

HN

N

O

(CH2)n

X = OH or NH2

Tc

biomolecule

FIG. 2.6. Tech19

nic complex may be transformed into a highly stable cationic plex (see Fig. 2.6).

the labelling technique required that the reaction mixture be rbon monoxide. A freeze-dried kit containing sodium tartrate,

orate, sodium carbonate and sodium boranocarbonate is now asy synthesis of Tc-carbonyl complexes. The transient (interme- is prepared by adding pertechnetate to the freeze-dried kit and boiling water for 20 min. In the second step, the reaction of the complex with the biomolecules containing a histamine or inal can take place at ambient temperature, providing mild labelling. Tricarbonyl labelling has been carried out with somato-ves [2.54], bombesin derivatives [2.55], neurotensin pseudo-, surface protein-B, isonitriles [2.57] and even glucose [2.58].

ED MOLECULES AND BIOCONJUGATES

logical specificity is one of the most important requirements of pharmaceuticals, and knowledge of the localization mechanism

eveloping optimal molecules. Systematic studies of receptorenantibody interactions can provide sufficient information for ed molecular modelling of potential bioconjugates. The ems not only may provide the ideal means of storing, visualizing ing molecular structures, but may also facilitate quantitative structural data, based on quantum chemistry. Thus, the bioactive olecular structure can be identified, giving an opportunity to

C

O NH

netium labelling of a biomolecule through the Tc-tricarbonyl synthon.

20

design, syntheinteractions.

For exa99mTc-TRODAthe cocaine moand TRODAT

As the fiand X. Concetechnetium, buthat of cocainemodifications, psychiatry [2.5

Technetiupreformed chpreformed checarboxyethyl dwith 2,3,5,6-tetof the biomole

The posBFCAs are copertechnetate technetium suthiolates (MAGcompounds) compounds) [fragments andcan be succeapproach.

NZ

Z = -COOCH3

X = -O-CO-Ph

Z = -CH2-[N2S2(Tc=O)]

X = -C6H4Cl

Cocaine TRODAT

Fsize and use small molecules appropriate for specific biological

mple, molecular design played an important role when T was developed for imaging Parkinsons disease. In this case, lecule was taken as a model. The structural similarity of cocaine is presented in Fig. 2.7.gure shows, there are some differences between substituents Z rning TRODAT, Z was designed as the complexing core for t the difference in X is to ensure a lipophilic character similar to , which would not be the case with substituent Z. With these 99mTc-TRODAT has become a successful agent in neuro-

9].m-99m labelled bioconjugates can be prepared by the

elate approach or by post-conjugation techniques. The first late approach was developed by Fritzberg et al. [2.60] when a erivative of an N2S2 core was transformed into an active ester rafluorophenol, followed by the reaction with the NH2 terminal cule (Fig. 2.8) [2.60]. t-conjugation labelling concept involves two steps: first, the upled efficiently with the bioactive compounds, and then either and a reducing agent or a freshly prepared weak complex of ch as gluconate or glucoheptonate is added. Triamidemono-

3-like compounds) [2.61], diaminodithiolates (BAT- or EC-like [2.62] and propyleneaminoxime derivatives (HMPAO-like 2.63] can be used as BFCAs. Peptides, monoclonal antibody other compounds such as spiperone derivatives or some steroids ssfully labelled with technetium using the post-conjugation

X

IG. 2.7. Structures of cocaine and technetiumTRODAT.

2.6. PRECURNEEDE

Increasintechnetium coprocedures toexample, prefofrom such prestable and hetricarbonyl lapreparation ofinto the solutavoided by us(ISOLINK).

Labellingreaction. The r

Conventiradiophaphate);

Weak che

Tartrate ligand exchanSn(II)-chlorideresulting in a

(Tc=O)N2S2-CH2CH2COOH + C6HF4OH carbodiimide (Tc=O)N2S2-CH2CH2COOC6HF4

+ -NH 2 (Tc=O)N2S2-CH2CH2CO-NH-

where (Tc=O)N2 S2- is

OO

biomolecule biomolecule

FIG. 2.8. Sy21

SORS AND CHELATING AGENTS D FOR THE LABELLING OF BIOMOLECULES

gly, laboratories are seeking to perform procedures with various mpounds prepared using novel labelling approaches. For such be successful, some practical issues must be addressed. For rmed chelators, including the technetium labelled active esters

cursors as tetrafluorophenol or tetrafluoro-thiophenol, are not nce need to be freshly prepared. Another issue concerning belling is the technique of obtaining carbon monoxide for the 99mTc-tricarbonyl synthon. Flushing carbon monoxide gas ion is a simple but not very convenient method that can be ing kit formulated, commercially available boranocarbonate

of biomolecules is often performed in the ligand exchange eaction partners can be divided into the following two groups:

onal ligand exchange partners, which originally were clinical rmaceuticals (e.g. kits of gluconate, glucoheptonate or pyrophos-

lators such as tartrate, citrate and EDTA.

was first used in the MAG3 kit as an ingredient for labelling by ge reaction. Tartaric acid neutralized with sodium hydroxide, and ascorbic acid (as a stabilizer) can be freeze-dried together, kit formulated agent for ligand exchange. This composition is

S

N N O

S

Tc

nthesis of a 99mTc labelled peptide by the post-conjugation technique.

22

available in the three-vial EC kit as well. EDTA is used as a ligand exchange partner in the ECD and MIBI kit, but it can be formulated separately as well.

In nitrido, HYNIC and tricarbonyl labelling, in addition to the biomol-ecule, co-ligands should be incorporated into the 99mTc complexes to attain the optimal structure and biological activity. In HYNIC labelling, first tricine and later EDDA were used in this way. Separate formulation of such co-ligands could be useful in the future.

[2.1] MELNIKcompoun

[2.2] LIBSON99Tc-diphimaging a

[2.3] BOYD, RRadiol. 4

[2.4] GUTKOspleen im

[2.5] ARNOLNucl. Me

[2.6] OHTA, Hcaptosucc105116.

[2.7] IKEDA, succinate1222122

[2.8] SUBRAMnate: A complexe

[2.9] BERGQ99mTc-DP

[2.10] SMITH, bleeding Med. 5 (1

[2.11] HARVEhepatobil

[2.12] ASCHERpropyl imlevels, ClREFERENCES TO SECTION 2

, M., VAN LIER, J.E., Analyses of structural data of technetium ds, Coord. Chem. Rev. 77 (1987) 275324., K., DEUTSCH, E., BARNETT, B.L., Structural characterization of a opsonate complex: Implications for the chemistry of 99mTc skeletal gents, J. Am. Chem. Soc. 102 (1980) 24782480..E., et al., 99mTc gluconate complexes for renal scintigraphy, Br. J.

6 (1973) 604612.WSKY, R.F., DWORKIN, H.J., Kit-produced 99mTc-labelled red cells for aging, J. Nucl. Med. 15 (1974) 11871191.

D, R.W., et al., Comparison of 99mTc complexes for renal imaging, J. d. 16 (1975) 357367.

., et al., Clinical evaluation of tumour imaging using 99mTc(V) dimer-inic acid, a new tumour-seeking agent, Nucl. Med. Commun. 9 (1988)

I., INOUE, O., KURATA, K., Preparation of various 99mTc dimercapto- complexes and their evaluation as radiotracers, J. Nucl. Med. 18 (1977) 9.

ANIAN, G., McAFEE, J.J., BLAIR, R., 99mTc methylenediphospho-superior agent for skeletal imaging Comparison with other Tc s, J. Nucl. Med. 16 (1977) 744754.

VIST, L., et al., Clinical comparison of bone scintigraphy with D, 99mTc-HDP, 99mTc-DPD, Acta Radiol. Diagn. 25 (1974) 217223.R.K., ARTERBURN, G., Detection and localization of gastrointestinal using 99mTc pyrophosphate in vivo labelled red blood cells, Clin. Nucl. 980) 5560.

Y, E., LOBERG, M.D., COOPER, M., A new radiopharmaceutical for iary imaging, J. Nucl. Med. 16 (1975) 533540., S.A., SARKAR, S.D., SPIVAK, W.B., Hepatic uptake of 99mTc diiso-inodiacetic (DISIDA) is not impaired by very high serum bilirubin

in. Nucl. Med. 13 (1988) 13.

[2.13] NUNN, A.D., LOBERG, M.D., CONLEY, R.A., A structure-distribution-relationship approach leading to the development of 99mTc mebrofenin: An improved cholescintigraphic agent, J. Nucl. Med. 24 (1983) 423430.

[2.14] DRUM, D.E., Current status of radiocolloid hepatic scintiphotography for space-occupying disease, Sem. Nucl. Med. 12 (1982) 6474.

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[2.16] WHATELEY, T.L., STEELE, G., Particle size and surface charge studies of a tin colloid ra353357.

[2.17] WATANAsulphide

[2.18] ARZOU99mTc-labtion, J. N

[2.19] TSOPELtrisulphidapplicatio

[2.20] AL-JANAtechniquekits to be(1983) 14

[2.21] BORMA99mTc-me

[2.22] NEIRINC99mTc-d,l-

[2.23] BANERJM.R.A., Oof in-houNucl. Me

[2.24] TUBERGtivity of (1991) 11

[2.25] WACKEHuman thallium-

[2.26] PROULXtion of ra(1989) 95

[2.27] SAVI, Ahumans, E

[2.28] KELLY, for myoc23

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BE, T., et al., Sentinel node biopsy with 99mTc colloidal rhenium in patients with breast cancer, Br. J. Surg. 88 (2001) 704707.MANIAN, A., ROSETHALL, L., SETO, H., Clinical comparison of elled preformed phytate colloid and sulfur colloid: Concise communica-ucl. Med. 18 (1977) 118120.AS, C., Particle size analysis of 99mTc-labelled and unlabelled antimony e and rhenium sulphide colloids intended for lymphoscintigraphic n, J. Nucl. Med. 42 (2001) 460466.BI, M.A., YOUSIF, Z.M., KADIM, A.H., AL-SALEM, A.M., A new

for the preparation of ready-to-use macroaggregated albumin (MAA) labelled with 99mTc for lung scanning, Int. J. Appl. Radiat. Isot. 34

731478.NS, G., et al., Investigation of the labelling characteristics of rcaptoacetyltriglicine, Nucl. Med. Biol. 22 (1995) 339349.

KX, R.D., Evaluation of regional cerebral blood flow with HMPAO and SPECT, Neurosurg. Rev. 10 (1987) 181184.EE, S., SAMUEL, G., KOTHARI, K., SARMA, H.D., PILLAI, n the synthesis, isolation and radiochemical studies for the preparation

se kit for 99mTc-meso- and d,l-HMPAO: A few additional observations, d. Biol. 26 (1999) 327338.

EN, K., CORLIJA, M., VOLKERT, W.A., HOLMES, R.A., Sensi-99mTc-d,l-HMPAO to radiolysis in aqueous solution, J. Nucl. Med. 321115.RS, F.J., et al., Technetium-99m hexakis 2-methoxyisobutyl isonitrile: biodistribution, dosimetry, safety and preliminary comparison to 201 for myocardial perfusion imaging, J. Nucl. Med. 30 (1989) 301311.

, A., BALLINGER, J.R., GULENCHYN, K.Y., Routine determina-diochemical purity of 99mTc-MIBI, Int. J. Rad. Appl. Instrum. A 40

97.., et al., Biodistribution of 99mTc methoxy-isobutyl-isonitrile (MIBI) in

ur. J. Nucl. Med. 15 (1989) 597600.J.D., et al., Technetium-99m-tetrofosmin as a new radiopharmaceutical ardial perfusion imaging, J. Nucl. Med. 34 (1993) 222227.

24

[2.29] NAKAJIMA, K., et al., Myocardial perfusion imaging and dynamic analysis with 99mTc tetrofosmin, J. Nucl. Med. 34 (1993) 14781484.

[2.30] ASENBAUM, S., BRUCKE, T., PIRKER, W., PIETRZYK, U., PODREGA, I., Imaging of cerebral blood flow with technetium-99m HMPAO and technetium-99m-ECD: A comparison, J. Nucl. Med. 39 (1998) 613618.

[2.31] KABASAKAL, L., Technetium-99m ethylene dicysteine: A new renal tubular function agent, Eur. J. Nucl. Med. 27 (2000) 351357.

[2.32] VAN NEROM, C.G., BORMANS, G.M., DE ROO, M.J., VERBRUGGEN, A.M., Firdicysteine

[2.33] KABASAtium-99m224228.

[2.34] NIELSENethylenedClin. Phy

[2.35] SUNBERChelating(1974) 58

[2.36] DELMOStrategietechnetiu

[2.37] BALDASof 99mTc-r

[2.38] PASQUApharmace334341.

[2.39] GHEZZIcomplex 1077.

[2.40] JOHNSOof technedial redis

[2.41] BELLANradiophaagents, N

[2.42] CALLAHFISHMAnicotinam(1996) 84

[2.43] RENNENCORSTE(HYNIC599604.st experience in healthy volunteers with technetium-99m L,L-ethylene-, a new renal imaging agent, Eur. J. Nucl. Med. 20 (1993) 738746.KAL, L., et al., Clinical comparison of technetium-99m-EC, techne-

-MAG3 and iodine-131-OIH in renal disorders, J. Nucl. Med. 36 (1995)

, S.S., et al., Clearance and renal extraction of technetium-99m-L,L-icysteine, I-131-ortho-iodohippurate and I-125-iothalamate in pigs,

siol. 19 (1999) 338343.G, M.W., MEARES, C.F., GOODWIN, D.A., DIAMANTI, C.I., agents for the binding of metal ions to macromolecules, Nature 2507588.N-MOINGEON, L.I., MAHMOOD, A., DAVISON, A., JONES, A.G., s for labelling monoclonal antibodies and antibody-like molecules with m-99m, J. Nucl. Biol. Med. 35 (1991) 4759., J., BONNYMAN, J., Effect of the Tc-nitrido group on the behaviour adiopharmaceuticals, Int. J. App. Radiat. Isot. 36 (1985) 919923.LINI, R., et al., Bis(sithiocarbamato) nitrido technetium-99m radio-uticals: Neutral myocardial imaging agents, J. Nucl. Med. 35 (1994)

, C., et al., Myocardial kinetics of TcN-NOET: A neutral lipophilic tracer for regional myocardial blood flow, J. Nucl. Med. 36 (1995) 1069

N, G., NGUYEN, K.N., PASQUALINI, R., OKADA, R.D., Interaction tium-99m NOET with blood elements: Potential mechanism of myocar-tribution, J. Nucl. Med. 38 (1997) 138143.DE, E., et al., Synthesis and biodistribution of nitrido technetium-99m

rmaceuticals with dithiophosphinate ligands: A class of brain imaging ucl. Med. Biol. 22 (1995) 315320.

AN, R.J., BARROW, S.A., ABRAMS, M.J., RUBIN, R.H., N, A.J., Biodistribution and dosimetry of technetium-99m hydrazino id IgG: Comparison with indium-111-DTPA-IgG, J. Nucl. Med. 37

3846., H.J., BOERMAN, O.C., KOENDERS, E.B., OYEN, V.J., NS, F.H., Labelling proteins with 99mTc via hydrazinonicotinamide

): Optimization of the conjugation reaction, Nucl. Med. Biol. 27 (2000)

[2.44] DECRISTOFORO, C., et al., 99mTc-EDDA/HYNIC-TOC: A new 99mTc-labelled radiopharmaceutical for imaging somatostatin receptor-positive tumours: First clinical results and intra-patient comparison with 111In-labelled octreotide derivatives, Eur. J. Nucl. Med. 27 (2000) 13181325.

[2.45] PLACHCINSKA, A., et al., Clinical usefulness of 99mTc-EDDA/HYNIC-TOC scintigraphy in oncological diagnostics: A preliminary communication, Eur. J. Nucl. Med. Mol. Imaging 30 (2003) 14021406.

[2.46] WELLING, M.M., et al., Radiochemical and biological characteristics of 99mTc-UBI 29-4

[2.47] RENNEN99mTc-labMed. 44 (

[2.48] LIU, S., Hhydrazinoinfection

[2.49] EDWARtinamide 10 (1999)

[2.50] SZEBENto doxil aRes. 12 (2

[2.51] GREENLBLOWEFmoc-N-tion to 99m

[2.52] ZHANGincreasesImaging B

[2.53] ALBERTthe labellin aqueou120 (1998

[2.54] MARMIPreparaticonjugate

[2.55] LA BELas potent

[2.56] GARCIAneuroten(2002) 37

[2.57] MARMI99mTc-(I)-Nucl. Me25

1 for imaging bacterial infections, Nucl. Med. Biol. 29 (2002) 413422., H.J., BOERMAN, O.C., OYEN, W.J., CORSTENS, F.H., Kinetics of

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R, P.J., Solid-phase synthesis of peptide radiopharmaceuticals using epsilon-(hynic-Boc)-lysine, a technetium-binding amino acid: Applica-Tc-labelled salmon calcitonin, J. Med. Chem. 46 (2003) 19511757.

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26

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[2.62] BAIDOOchelatingBioconju

[2.63] LINDERcontaininzation an

3.

The manpharmaceuticaof the pharmalicensed for co

3.1. MAIN C

Good mincluding:

Adequat Appropr Clear def Validatio Validatio Approve

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, K.E., LEVER, S.Z., Synthesis of diaminedithiol bifunctional agent for incorporation of technetium-99m into biomolecules, g. Chem. 1 (1990) 132137., K.E., et al., TcO/PnAO-1-(2-nitromidazole)/, A new technetium g nitroimidazole complex for imaging hypoxia: Synthesis, characteri-d xanthine oxydase-catalyzed reduction, J. Med. Chem. 37 (1994) 917.

GOOD MANUFACTURING PRACTICE

ufacture of kits is currently considered to be conventional l production and hence needs to fulfil all the basic requirements ceutical industry. Consequently, manufacturers of kits should be mpliance with GMP by the regulatory authorities.

OMPONENTS OF GMP

anufacturing practice involves requirements in several areas,

e premises, space, equipment and materials;iately qualified and trained personnel; inition of manufacturing processes;n of critical steps in the process; n of any significant changes to the process;d instructions and procedures for production, quality control oduct release, etc.;

Quality assurance (QA) and QC activities, independent of production; Records of manufacture and complete batch history; Controlled product release; Suitable storage and transport of finished products; Means to recall any batch from sale or supply; Examination of complaints and investigation of quality defects.

3.2. QUALIT

All activcontrolled by tbasic concept ocollectively, maorganized arra(i.e. the safetymust be perfoabove. QC acstarting materproducts. It avalidated test/a

3.3. PERSON

3.3.1. Key p

The folloproduction setqualified perso

The HP exist and apprensures that thare made, and

The HQCbulk and finiscarried out, evalidations of a

The QP,authorities, enthe pertinent d27

Y MANAGEMENT

ities of kit production (i.e. pharmaceutical production) are he quality management system (QMS), based on an interrelated f QA, GMP and QC. QA covers all matters that, individually or y influence the quality of the product. Thus QA is the totality of

ngements for ensuring the quality required for the intended use of pharmaceutical products). To implement QA, all activities rmed according to the rules of GMP covering the areas listed tivity covers all sampling, testing and monitoring, including ials, packaging materials, and intermediate, bulk and finished lso requires that trained personnel be employed and that nalytical methods and approved procedures be used.

NEL

ersonnel

wing three persons are considered to be key personnel in a up: the head of production (HP), the head of QC (HQC) and the n (QP).

ensures that appropriate conditions for production and storage oves the standard operating procedures (SOPs). The HP also e appropriate validations and evaluations of production records checks that equipment is properly maintained. approves or rejects the starting and packaging materials, and

hed products. He or she ensures that all necessary tests are valuates the analytical records and ensures the appropriate nalytical procedures.

who is approved by the local pharmaceutical regulatory sures that every batch is produced and tested in accordance with irectives and specifications, and releases all batches.

28

3.3.2. Training

The manufacturer must provide basic training for all personnel and special training to certain groups of personnel according to their assigned duties. The training programme has to be planned for each year and performed several times a year. Personnel deployed for kit preparation should have a university degree in chemistry, radiochemistry or pharmacy, and all support personnel shou

3.3.3. Person

Regular should be ppreparation is lesions, injurieclothing, handproduction and

3.3.4. Organ

The QMSreason, QA anto be independQA, the HQCby the QP is thof the QP is baas well as the GMP organizamentioned fun

3.4. PREMIS

3.4.1. Premi

Kit prepcleanliness critto the grade oTable 3.1.ld be trained in GMP.

nel hygiene

medical examinations of the personnel involved in production erformed and registered. Involvement in pharmaceutical prohibited in the case of illness (e.g. infectious diseases, open

s). Sterile/aseptic conditions are to be maintained by appropriate washing and disinfection. Eating, drinking and smoking in storage areas are prohibited.

ization and functions

requires clearly defined functions and responsibilities. For this d production should be completely separate that is, they have ent units of the manufacturer. While QC may be a sub-unit of

and the QP must be two different persons. Thus, product release e crucial step in pharmaceutical production. The release decision sed on evaluation of the analytical and batch processing records environmental monitoring results. A schematic presentation of tion and functions is given in Fig. 3.1. In the figure, the above ctions are represented by dashed arrows.

ES AND EQUIPMENT

ses

aration must be performed on premises meeting defined eria. Production areas can be divided into four groups according f sterility/aseptic conditions. This classification is presented in

Since kitaseptic prepara

HandlingThe item

Measuringrade C a

Aseptic filtering aarea is nobackgrou

TABLE 3.1. CISO-14644 STA

ISO class

Grade

5 A (10

6 B (1 0

7 C (10

8 D (10

Chief of company or institute

Quality assurance Pharmaceutical production

Quality control

Qualifie

Analytical records, Batch processing records

Other units

FIG. 3.29

s cannot be sterilized terminally (i.e. in their final containers), tion is required. This means that:

of items after washing should be performed in a grade D area. s will be sterilized before use.g of chemicals for solutions to be filtered should be done in a rea.

preparation (that is, making solutions, setting the pH, sterile nd dispensing) is to be carried out in a grade A area. (A grade B t a dedicated area for any operation; it can be considered as the

nd area or buffer zone for a grade A quality laminar flow bench.)

LEAN AIR CLASSIFICATIONS WITH REFERENCE TO NDARDS

(class)

Maximum permitted number of particles/m3 of air

At rest In operation

Particles

30

The controlled areas should be provided with an air supply that is filtered through a microbe retaining filter and enters through an airlock. To ensure a grade A area for aseptic preparation, a laminar flow bench is necessary. Material transport into the grade A area should be performed either via the transport window of an interlocking system (chemical and previously sterilized and hermetically packed items) or via the dual door heat sterilizer (items to be heat sterilized). The freeze-dryer should be placed outside the grade A area; only the door freeze-drying mclosing, the viwindow with abe represented

In Fig. 3.Lower grade ato enter the graof laboratory gshould be sepagrades. Beforeparticulate conhigh grade of aprepared in thdispensed in th

A typicalin Fig. 3.3.

The condThe pressure dpressure differregistered. Thedifferent areas

Althoughindustry, avoidyeast is criticaables. Recommduring operati

Figures 3turing facility. turing zone aftthe clean roomis a dispensingof the freeze-dryer and the space where the vials are put for ay be in contact with the grade A area. After freeze-drying and

als can leave the grade A area through a different transfer n interlocking system for packaging. Thus the material flow can as a single direction line that does not cross the other flow lines.2, the concept of the clean room design is presented graphically. reas surround the higher grade areas. It should not be possibile de A area from grade C or lower areas without a proper change owns in changing rooms. The flow of materials and personnel

rated. Pass boxes should be installed between rooms of different entering the grade B area, an air shower is needed to remove tamination from personnel after gowning and to maintain the ir purity when entering the grade B room. Bulk solution can be

e grade C area, but its sterility must be assured before it can be e grade A area by sterile filtration. layout of a clean room facility for the production of kits is given

itions of the production area must be controlled and monitored. ifference before and after the air filters must be checked, and

ences between the areas of different grades must be checked and temperature also needs to be controlled, and air samples from must be collected and evaluated regularly. the control of particulates is important for the pharmaceutical ing contamination of products by microorganisms, bacteria or l in terms of the premises involved in the production of inject-

ended limits for microbiological monitoring of clean areas on are given in Table 3.2..4(a)(c) are typical views of a GMP compliant kit manufac-

Figure 3.4(a) shows a worker ready to enter the aseptic manufac-er changing into sterile attire. Figure 3.4(b) shows the inside of and the loading chambers of the two freeze-dryers. Figure 3.4(c) operation under a laminar flow station using a semi-automatic

dispenser. Notlaboratory.

Apart frdesignated formaterials, sepaand excipientswith the pharmboxes, labels). to avoid any coair humidity squarantine, apseparately. Thstorage.

Product

Personnel

FIG. 3.2. CleaSF: sterile filtrati31

e that only the minimum essential equipment is provided in the

om the clean room for dispensing, separate stores should be starting materials and finished products. Regarding starting rate places should be defined for chemicals (active ingredients ), primary packaging materials (vials and stoppers in contact aceutical products) and secondary packaging materials (paper

Laminar flow should be ensured in the store for chemicals so as ntamination during their sampling. Controlled temperature and hould be provided in the starting material store. Places for proved products and rejected products should be provided

ese places should also be distinguished from finished product

Materials

Substances

n room concept; AS: air shower; CR: changing room, PB: pass box; on.

32

3.4.2. Equip

All equimembrane filtlaminar flow bthis equipmen

TABLE 3.2. MCLEAN ARE

Grade (class)

A (100)

B (1 000)

C (10 000)

D (100 000)

Note: CF