June 2020 | Investor Presentation

Spectrum Pharmaceuticals

A Biopharmaceutical Company Developing Targeted and Novel Therapies in Oncology

Joe Turgeon | President and CEO

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Safe Harbor StatementThis presentation contains forward-looking statements regarding future events and the future performance of Spectrum Pharmaceuticals that involve risks and uncertainties that could cause actual results to differ materially. These statements are based on management’s current beliefs and expectations. These statements include but are not limited to statements that relate to our business and its future, our strategy, the success of our drug candidates, the safety and efficacy of our drug products, product approvals, market potential, product sales, revenue, development, regulatory and approval timelines, product launches, product acquisitions, capital resources and any statements that relate to the intent, belief, plans or expectations of Spectrum or its management, or that are not a statement of historical fact.

Risks that could cause actual results to differ include the possibility that our existing and new drug candidates may not prove safe or effective, the possibility that our existing and new drug candidates may not receive approval from the FDA and other regulatory agencies in a timely manner or at all, the possibility that our existing and new drug candidates, if approved, may not be more effective, safer or more cost efficient than competing drugs, the possibility that price and other competitive pressures may make the marketing and sale of our drugs not commercially feasible, the possibility that our efforts to acquire or in-license and develop additional drug candidates may fail, our lack of sustained revenue history, our limited experience in establishing strategic alliances, our limited marketing experience, our customer concentration, the possibility for fluctuations in customer orders, evolving market dynamics, our dependence on third parties for clinical trials, manufacturing, distribution, information and quality control and other risks that are described in further detail in the Company's reports filed with the Securities and Exchange Commission. We do not plan to update any such forward-looking statements and expressly disclaim any duty to update the information contained in this presentation except as required by law.

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Targeted & Novel MedicinesSpectrum’s Pipeline

Focused InterferonTherapeutics (FIT)Phase 1 Dose Escalation Study

POZIOTINIB

Cohort 2 Results Mid-2020

ROLONTIS®

(eflapegrastim)

PDUFA Date of October 24, 2020

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ROLONTIS® (eflapegrastim)

BLA has been accepted with a PDUFA of Oct 24th 2020

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ROLONTIS is a Novel Product with a Unique Molecular Structure

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Robust Data Set Features Head to Head Data vs Neulasta

* Non-inferiority of ROLONTIS versus pegfilgrastim in Duration of Severe Neutropenia in Cycle 1** 95% confidence intervals and p-value obtained from bootstrap sampling method

ADVANCE (-301) RECOVER (-302)

ROLONTISN=196

PegfilgrastimN=210

ROLONTISN=118

PegfilgrastimN=119

DSN (days)Mean (SD)Median (Range)

0.20 (0.503)0 (0, 3)

0.35 (0.683)0 (0, 3)

0.31 (0.688)0 (0,3)

0.39 (0.949)0 (0,7)

Δ DSN (SPI-2012 –pegfilgrastim)95% Confidence Interval**Non-inferiority p-value**

-0.148(-0.264, -0.032)

<0.0001

-0.074(-0.292, 0.129)

<0.0001

643 Patients in Two Phase 3 Trials

Met Primary

Endpoint*

Met All Secondary Endpoints

Similar AE Profile

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Integrated Phase 3 Results Presented at ASCO 2019

Incidence of Severe Neutropenia from Two Phase 3 ROLONTIS Trials

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Long Acting G-CSF Market Presents a Compelling Opportunity

Customer Behavior

Reimbursement Dynamics

Market Size

>$3B total US market value Rational pricing behavior among competitors NCCN Guidelines recently revised to recommend

increased use of G-CSF

Willingness to change products based on value Onpro® volume declining with pre-filled syringe growth Providers receptive to incremental contracting opportunities

Unique reimbursement for novel products is a competitive advantage

Value based care creates additional complexity in customer’s decision matrix

Commercial payers increasingly important stakeholders in decision-making

Neulasta 73%

Udenyca, 21%

Fulphila, 6%

Estimated LA-GCSF Market Share: Current 3 months through Jan 2020

Market Landscape

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Pricing: Q2 2020

Neulasta WAC $6,231

Neulasta ASP$3,758

Biosimilars ASPs are 3-8% below

Neulasta

Biosimilars ASP

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Poziotinib

Tyrosine Kinase Inhibitor targeting mutations in lung

cancer

Results from ZENITH20 cohort 2 in mid-2020

Results from ZENITH20 cohort 3 in 2H 2020

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Unique Structure Provides Irreversible Binding

Poziotinib

Even with the restricted binding pocket of exon 20 mutations, preclinical studies have shown that poziotinib is able to overcome steric hindrance allowing for irreversible binding

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Cohort 1 Results

Best Overall Response Intent to treat (N=115)N (%)

Objective Response Rate (ORR) by independent review committee (IRC)95% Confidence Interval

17 (14.8%)(8.9 - 22.6%)

Disease Control Rate (DCR=CR+PR+SD)95% Confidence Interval

79 (68.7%)(59.4 - 77.0%)

Duration of Response, Median (months)95% Confidence Interval

7.4(3.7, 9.7)

Progression-free Survival, Median (months)95% Confidence Interval

4.2(3.7, 6.6)

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ZENITH 20 Cohort 1 Waterfall PlotBest Percent Change from Baseline in Sum of Longest Diameter by Treatment Group

*Indicates subject is ongoing treatment

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Safety: Treatment-related Adverse Events

Drug interruption rate 88%

Dose reduction rate 68%

Permanent discontinuation due to

treatment-related AE = 12 (10%)

No Grade 5 treatment related AE

Most common treatment-related

AEs (any grade) include:

Rash

Diarrhea

Stomatitis

Paronychia

Treatment-related AEN=115

Any Grade n (%)

Grade 3 n (%)

Grade 4 n (%)

Any TRAE 114 (99) 70 (61) 2 (2)Diarrhea 91 (79) 29 (25) 1 (1)Rash 69 (60) 32 (28) 0Stomatitis 60 (52) 10 (9) 0Paronychia 52 (45) 7 (6) 0Nausea 44 (38) 3 (3) 0Decreased appetite 36 (31) 2 (2) 0Mucosal inflammation 34 (30) 8 (7) 0Dry skin 33 (29) 3 (3) 0Vomiting 33 (29) 1 (1) 0Alopecia 31 (27) 0 0Dermatitis acneiform 30 (26) 8 (7) 1 (1)Fatigue 30 (26) 6 (5) 0Pruritus 29 (25) 5 (4) 0

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Efficacy: Duration of Response

Response ProgressionTreatment ongoing

16 mg 14 mg12 mg10 or less

0 28 56 84 112 140 168 196 224 252 280 308 336 364 392

Days

Median duration of response:

7.4 months

(95% CI 3.7,9.7)

Responses occurred early and were durable

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Simulated Poziotinib Plasma Concentrations8 mg BID vs. 16 mg QD

Pozi plasma ½ life is 7.9 hours

BID dosing

Decreases Cmax

Maintains Ctroughabove IC50

Pozi IC50 4nM (2ng/ml)-T790m

00

10

20

30

40

50

60

70

Subject US010-002(Simulated Concentrations)

Time (Days)1 2 3 4 5

16 mg QD8 mg Q12H

IC50

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ZENITH20: Continued Enrollment with New Cohorts

Key Eligibility Criteria

NSCLC EGFR or HER2 exon20 insertions

Point mutations, including T790M, are not allowed

Brain mets are allowed if stable

Cohort 1EGFR - previously treated

Cohort 2HER2 - previously treated Primary Endpoint

Objective Response Rate (RECIST 1.1)

Secondary Endpoints Duration of

response Disease control rate PFS (exploratory) Safety

NSCLC patients with EGFR or HER2 Mutations

Cohort 3EGFR – treatment naive

Cohort 4HER2 – treatment naive

16mg QD

Cohort 5EGFR or HER2 exon 20

Cohort 6EGFR osimertinib failure

Cohort 7Atypical EGFR or HER2

mutations

8mg BID

Osimertinib-resistant with

EGFR mutationsAtypical EGFR or HER2

mutations

Randomized to 10mg QD, 6mg BID, 8mg BID

Oral daily dose 28-day cycle

8mg BID

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Exon 20 Mutations in Various Tumor Types

Prevalence of Exon20 NSCLC in Key Markets

Region Mutation Exon 20 Frequency (%)

Total Number of Exon-20 NSCLC Patients/year

USEGFR 2.1%

3.6% 7,700HER2 1.5%

EUEGFR 2.1%

3.6% 8,000HER2 1.5%

JapanEGFR 2.4%

6.4% 5,000HER2 3.9%

TOTAL Patients 20,700

Prevalence of Exon20 In Other Tumors

Region MutationExon 20

Frequency (%)

Total Exon 20 (non-Lung) Patients/year

US

EGFR 3710 (0.2%)

0.6% 8,400

HER2 4691 (0.4%)

Heymach J. Phase II trial of poziotinib for EGFR and HER2 exon 20 mutant NSCLC Presented at IASLC 19th World Conference on Lung Cancer; Sept. 2018 Toronto CAN

N= 390,000 patients

Total US Patients 8,400Total Global Patients 20,700

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Focused Interferon Therapeutics

IFN is an approved treatment for cancer

But systemic IFN therapy has limitations due to dose limiting toxicity

Focused IFN Therapeutics (FIT) Technology seeks to overcome the toxicity while maintaining efficacy

By attaching IFN to an antibody, FIT targets delivery of IFN to tumor microenvironment

FIT Platform

Targeted Antibody-InterferonFusion Technology

FIT – Fusion of Interferon (IFNα) and Targeted Antibodies

Unaltered binding to Fc receptor

Growth inhibition Turn cold tumors into HOT Direct Apoptosis

Proteolysis-resistant short peptide LINKER

Interferon(IFN)

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Mechanism of Action

NO Apoptosis/Growth arrest

Ab-IFN binds poorly to IFN-R

No IFN-Rsignaling

IFN Target antigen

Antibody does not bind cell surface antigen

Normal Cells without Antibody Target

Apoptosis/Growth arrest

1

Antibody binds target

IFN binds IFN-R

IFN-Rsignaling

IFN Target antigen

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Tumor Cells with Antibody Target

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Lead Asset in Phase 1 Study

Phase 1, Open-Label, Dose-Escalation Study in Subjects with Refractory Non-Hodgkin Lymphoma⁻ Evaluate the Safety, Tolerability, and PK of Multiple IV Doses with Weekly

Administration⁻ Planned for up to 20 subject at maximum tolerated dose

Primary Outcome Measures⁻ Safety and tolerability (weekly for 6 months)⁻ Determine the maximum tolerated dose

Secondary Outcome Measures⁻ Characterize PK/PD profile of ascending doses⁻ Anti-tumor activity

Clinical Trial Sites⁻ UCLA, University of Florida, MD Anderson Cancer Center

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Targeted & Novel MedicinesSpectrum’s Pipeline

Focused InterferonTherapeutics (FIT)Phase 1 Dose Escalation Study

POZIOTINIB

Cohort 2 Results Mid-2020

ROLONTIS®

(eflapegrastim)

PDUFA Date of October 24, 2020

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Thank you

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Non-GAAP Financial Measures (from Continuing Operations)

In this press release, Spectrum reports certain historical results that have not been prepared in accordance with generally accepted accounting principles (GAAP), including non-GAAP selling, general and administrative expenses, non-GAAP research and development expenses, non-GAAP net loss and non-GAAP net loss per share. Non-GAAP financial measures are reconciled to the most directly comparable GAAP financial measures in the tables of this press release and the accompanying footnotes. The non-GAAP financial measures contained herein are a supplement to the corresponding financial measures prepared in accordance with GAAP. The non-GAAP financial measures presented exclude the items summarized in the below table.

Management believes that adjustments for these items assist investors in making comparisons of period-to-period operating results and that these items are not indicative of the company's on-going core operating performance. Management uses non-GAAP net income (loss) in its evaluation of the company's core after-tax results of operations and trends between fiscal periods and believes that these measures are important components of its internal performance measurement process. Management believes that these non-GAAP financial measures are useful to investors in providing greater transparency to the information used by management in its operational decision-making. Management believes that the use of these non-GAAP financial measures also facilitates a comparison of the company’s underlying operating performance with that of other companies in its industry, which use similar non-GAAP measures to supplement their GAAP results.

The non-GAAP financial measures presented herein have certain limitations in that they do not reflect all of the costs associated with the operations of the company's business as determined in accordance with GAAP. Therefore, investors should consider non-GAAP financial measures in addition to, and not as a substitute for, or as superior to, measures of financial performance prepared in accordance with GAAP. In addition, other companies, including other companies in our industry, may calculate non-GAAP financial measures differently than we do, limiting their usefulness as a comparative tool. Investors and potential investors are encouraged to review the reconciliation of our non-GAAP financial measures contained within this news release with our GAAP financial results.

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