November 2016

Forward-looking statements

This presentation contains forward-looking statements. These forward-looking statements are subject to risks and uncertainties, including the factors described under the Risk Factors section of our Quarterly Report on form 10-Q filed with the Securities and Exchange Commission on November 9, 2016 and made available on our website at www.agenusbio.com. When evaluating Agenus’ business and prospects, careful consideration should be given to these risks and uncertainties. These statements speak only as of the date of this presentation, and Agenus undertakes no obligation to update or revise these statements. This presentation and the information contained herein do not constitute an offer or solicitation of an offer for sale of any securities.

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Cancer immunotherapy: Curative

SOC = standard of careCP = checkpointSOC

Ipilimumab

Ipilimumab +Anti-PD-1

Time

% S

urvi

val

0

100

• Vaccine + Checkpoint Abs• Novel CP Ab combos

3

4

New clinical development paradigm compressed

Conventional time to BLA

Ris

k

AGEN1884 / AGEN2034 Solid TumorsEfficacy proven

AGEN1884 / AGEN2034

Solid TumorsEfficacy

unknown

AGEN1884 / AGEN2034

+Vaccine

AGEN1884 / AGEN2034

+ Novel CP

mAb (A, B, C)

10 years

AGEN1884 = anti-CTLA-4 mAbAGEN2034 = anti-PD-1 mAbCP = checkpoint

5

Agenus 2016

• Clinical Stage: • mAbs – CTLA-4*, PD-1*^, GITR**, OX40**^

• Vaccines – Prophage™, AutoSynVax™^

• In-house capabilities:• Full Research and Development capabilities• Cell line development• GMP mAb and vaccine production• I-O drug development expertise

• Filed:• GSK’s shingles vaccine with QS-21 Stimulon®+

* CTLA-4 and PD-1 mAbs are partnered with Recepta for certain South American territories.** GITR and OX40 mAbs are partnered with INCY.^ OX40, PD-1 and AutoSynVax™ expected to enter the clinic within the next 6 months.+ Royalty monetization announced Q3 2015.

• I-O Combination portfolio • mAbs, vaccines, adjuvants

• In-house capabilities - speed, quality, efficiency:

• Discovery/Research• Cell line development• GMP manufacturing

• Commercial ready• Readiness for FIM to filing< 4 years

Future Success in I-O

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Current partnerships

• 1 undisclosed target• Lead selection completed• Mid-single digit royalties with up to $100 million in milestones

• Pre-clinical: LAG-3, TIM-3, 3 undisclosed• Clinical: GITR, OX40*• 50/50** cost and profit share• Royalty rates are generally 6-12 % and up to $350 million in

milestones across the 4 programs.

• QS-21 Stimulon®: adjuvant for Shingrix®

• Filed for registration in U.S.• Royalties and milestones partly monetized

* OX40 agonist expected to enter clinical development in Q4 2016.** Specific to the OX40 and GITR programs.

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Agenus 2017-2021

• #1 Priority: Advance on most rapid path to BLA• Develop, register, and launch PD-1/CTLA-4 mAb combinations in validated

indications

• #2 Priority: Leverage novel targets for market expansion• Advance novel I-O mAb and vaccine combinations with CTLA-4 +/- PD-1• Advance partnered programs (GITR, OX40, TIM-3, LAG-3) towards registration• Enter into strategic partnerships to advance the above as well as all other

programs in certain territories

Combination TherapyClinical Strategy

Jennifer Buell, Ph.D.,VP, Global Research & Development Operations

Broad I-O portfolio

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[CTLA-4] + [PD-1] first clinically validated I-O combo

*Anti-CTLA-4 antibody AGEN1884 is partnered with Recepta for certain South American territories

• CTLA-4 (low dose) combined with PD-1/PD-L1 is the only validated combination with improved efficacy and safety profile

• Doubling of clinical response - from ~25% to 40% in non-small cell lung cancer(1,2)

• Control of CTLA-4 + PD-1/PD-L1 therapies gives pricing advantage

• Enables novel checkpoint mAbs that are yet to show efficacy in the absence of

CTLA-4

1. 2016 ASCO Annual Meeting; CheckMate -012 study; abstract no. 30012. BMS press release 06/04/2016

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PD-1 has clinical benefit but adding CTLA-4 works better

*Anti-CTLA-4 antibody AGEN1884 is partnered with Recepta for certain South American territories

• CTLA-4 (low dose) combination with PD-1/PD-L1 reduces development risk and expands markets• CTLA-4 and PD-1 combination is already approved in metastatic melanoma

• CTLA-4 and PD-1 combination doubles clinical benefit in 1L NSCLC(1,2)

• CTLA-4 + PD-1/PD-L1 +/- novel CPs has shown compelling data in pre-clinical models

1. 2016 ASCO Annual Meeting; CheckMate -012 study; abstract no. 30012. BMS press release 06/04/2016

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Agenus CTLA-4 and PD-1 antagonists CTLA-4 + PD-1 combination - focal point of next generation of I-O combos

*Anti-CTLA-4 antibody AGEN1884 is partnered with Recepta for certain South American territories

AGEN1884*:

• The only known CTLA-4 Ab in the clinic outside of big pharma (BMS and AZN)

AGEN2034*:

• PD-1 antagonist anticipated to enter clinical development Q1 2017

Agenus - only known company other than BMS with both in clinical stage

* AGEN1884 and AGEN2034 are partnered with Recepta for certain South American Rights

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Median per tumor

The Challenge: extending the benefits of I-O to more cancer patients

Phosphotopes + CPMs Vaccines + CPMs CPM Combinations

Clinical benefit of combinations

• Validated combinations:

• CTLA-4 + PD-1

• Next generation:

• CTLA-4 + PD-1 + Novel mAbs

• CTLA-4 + PD-1 + Vaccines

• Ipilimumab monotherapy failed in Ph 3(1), BUT, Vaccine + Ipi combination showed benefit; 20% of patients alive at 80 months(2,3)

(1) Kwon et al., Lancet Oncol 2014; 15(7); 700-12.(2) 2015 Genitourinary Cancers Symposium, abstract no. 172;(3) Bavarian Nordic press release 02/24/2015..

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Agenus CTLA-4 mAb improves primate vaccine response

-7 1 5 2 9 4 3 5 9 6 90

5 0 0 ,0 0 0

1 ,0 0 0 ,0 0 0

1 ,5 0 0 ,0 0 0

2 ,0 0 0 ,0 0 0

Ant

i-HB

sAg

IgG

(U/m

L)

C o n tr o l (N = 6 )

A G E N 1 8 8 4 (N = 6 )

D a y s A fte r In itia l D o s in g

A d m in is tra tio n s o f an tib o d yo r v e h ic le (c o n tro l)p lu s H B s A g v a c c in e

Anti-CTLA-4 antibody AGEN1884+

Hepatitis B surface antigen (HBsAg) vaccine

Internal data (unpublished)

VaccineAntibody

-4 0 8 1 5 2 2 2 9 3 6 4 3 5 0 5 7 6 7

0

1 0 0

2 0 0

3 0 0

4 0 0

5 0 0

SFU/

1x10

6 PBM

C

Is o ty p e c o n tro lA G E N 1 8 8 4

Humoral Response Cellular Response

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CTLA-4 is critical in combination with other I-O modalities

AGEN anti-CTLA-4 (1884) in combination with anti-PD-1 enhances T cell response of Pembro and Nivoalone

Anti-CTLA-4 AGEN Vaccine combination enhances anti-tumor response

CTLA-4 + AutoSynVax™

0

5 0 0

1 0 0 0

1 5 0 0

2 0 0 0

A n tib o d ie s T e s te d

IL-2

(p

g/m

L)

a n ti-LA G 3 N ivo lu m ab P e m b ro liz u m a b

Iso type

A nti-LA G -3

A G E N 1884

C o m b in a tio n

Iso type

N ivo lu m ab

A G E N 1884

C o m b in a tio n

Iso tpye

P re m b ro liz u m a b

A G E N 1884

C o m b in a tio n

0

5 0 0

1 0 0 0

1 5 0 0

2 0 0 0

A n tib o d ie s T e s te d

IL-2

(p

g/m

L)

a n ti-LA G 3 N ivo lu m ab P e m b ro liz u m a b

Iso type

A nti-LA G -3

A G E N 1884

C o m b in a tio n

Iso type

N ivo lu m ab

A G E N 1884

C o m b in a tio n

Iso tpye

P re m b ro liz u m a b

A G E N 1884

C o m b in a tio n

0

5 0 0

1 0 0 0

1 5 0 0

2 0 0 0

A n tib o d ie s T e s te d

IL-2

(p

g/m

L)

a n ti-LA G 3 N ivo lu m ab P e m b ro liz u m a b

Iso type

A nti-LA G -3

A G E N 1884

C o m b in a tio n

Iso type

N ivo lu m ab

A G E N 1884

C o m b in a tio n

Iso tpye

P re m b ro liz u m a b

A G E N 1884

C o m b in a tio n

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anti-CTLA-4 + GITR agonist enhanced anti-tumor response

CTLA-4 is critical in enhancing novel combinations

(1) Madan RA, et al. Lancet Onc. 2012; 3:501-508(2) Pinto, et al.ASCO-GU poster 2015(3) Avogadri F. et al. Curr Top Mic. Immunol. 2011(4) Kuibeom et al. JEM. 2005(5) Marabelle A (Levy) et al., JCI 2013(6) Chapuis A.G. et al. JCO 2015.65.5142

anti-CTLA-4 / cell therapy demonstrates robust disease response

• Next generation combinations:

• CTLA-4 + GITR Agonist

• CTLA-4 + Cell Therapy

17

18

New clinical development paradigm compressed

Conventional time to BLA

Ris

k

AGEN1884 / AGEN2034 Solid TumorsEfficacy proven

AGEN1884 / AGEN2034

Solid TumorsEfficacy

unknown

AGEN1884 / AGEN2034

+Vaccine

AGEN1884 / AGEN2034

+ Novel CP

mAb (A, B, C)

10 years

AGEN1884 = anti-CTLA-4 mAbAGEN2034 = anti-PD-1 mAbCP = checkpoint

AGEN2034: projected clinical inflection points

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Broad I-O portfolio

20

Broad I-O portfolio: opportunistic

21

Business

Garo Armen, Ph.D.,Chairman & CEO

2016 2017 2018Accomplishments

• 2 CP mAbs in clinic• CTLA-4 (AGEN1884)• GITR (INCAGN1876)

• Advance 3 more programs to clinic next 6 months

• OX40 (INCAGN1949) • PD-1 (AGEN2034) • ASV™ (AutoSynVax™)

• 3 Clinical mAbs selected and IND studies ongoing

• Clinical Development team with I-O development success on board

• QS-21 Stimulon® containing Shingles vaccine filed for regulatory approval

• INCY collaboration expanded

Clinical Deliverables

Clinical trials• Initiate Ph 1 for PD-1 monotherapy• Initiate virally-induced cancer trial

(2L)• Ph 1b with anti-PD-1 + anti-CTLA-4• Ph 1 with AutoSynVax™

• Clinical results • Optimal dose for anti-PD-1 n~10 at

each dose level• Optimal combination dose of anti-

PD-1 + anti-CTLA-4

• Clinical responses• Results from 30 patients in the

virally-induced cancer cohort (2L)

Clinical Activity & Readouts

• Enrollment complete for 2nd line virally-induced cancer cohort

• Top line data for the virally-induced cancer cohort:

• response rate • duration of response • safety and tolerability

Projected milestones

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Management Team• Garo Armen, PhD, Chairman & CEO

Elan Corporation, plc, Protagenic Therapeutics, Founder - Children of Armenia Fund (COAF)

• Robert Stein, MD, PhD, President, R&DIncyte Pharmaceuticals, Ligand Pharmaceuticals, Dupont/Merck, Roche, KineMed, Merck, Sharp & Dohme

• Jennifer Buell, PhD, VP Research & Development OperationsHarvard Clinical Research, Bristol-Myers Squibb

• Christian Cortis, PhD, VP Business DevelopmentSynta Pharmaceuticals, Advanced Technology Ventures, Columbia University

• Jean-Marie Cuillerot, MD, VP & Global Head of Clinical DevelopmentEMD Serono, Bristol-Myers Squibb, University Louis Pasteur

• Alex Duncan, PhD, Chief Technology OfficerActigen, Affitech A/S, Astra Zeneca, Cambridge Antibody Technology

• James Gorman, MD, PhD, VP Strategic Planning & Portfolio ManagementAbbott Laboratories, Harvard University

• Christine Klaskin, VP FinanceArthur Andersen, George Washington University

• Karen Valentine, JD, Chief Legal Officer & General Counsel Palmer and Dodge LLP