Agios Reports Business Highlights and Third Quarter 2020 Financial Results Third Quarter TIBSOVO Net Revenue of $31.7 Million; Company Narrows 2020 TIBSOVO Net U.S. Revenue Guidance to $113 115 Million Topline Data from

Agios Reports Business Highlights and Third Quarter 2020 Financial Results

Third Quarter TIBSOVO Net Revenue of $31.7 Million; Company

Narrows 2020 TIBSOVO Net U.S. Revenue Guidance to $113 115 Million

Topline Data from the Mitapivat Phase 3 ACTIVATE Trial in Non-Transfusion Dependent PK

Deficiency Expected by Year-End; Topline Phase 3 ACTIVATE-T Data Expected in Q1 2021

Reported Positive Overall Survival Trend in ClarIDHy Phase 3 Trial of

TIBSOVO in Advanced Cholangiocarcinoma; Company Plans to Submit Supplemental New Drug Application in Q1 2021

CAMBRIDGE, Mass., November 5, 2020 Agios Pharmaceuticals, Inc. (NASDAQ: AGIO), a leader in the field of cellular metabolism

to treat cancer and rare genetic diseases, today reported business highlights and financial results for the third quarter ended September 30, 2020.

In the third quarter, we made significant strides toward executing against our key 2020 priorities and getting our medicines to patients who need

them, said Jackie Fouse, Ph.D., chief executive officer at Agios. Most notably, we generated mature overall survival data from our Phase 3 ClarIDHy study of TIBSOVO in previously

treated cholangiocarcinoma, prepared for topline data readouts from our two global Phase 3 studies of mitapivat in pyruvate kinase deficiency and advanced our pivotal plans for mitapivat in thalassemia and sickle cell disease. We look forward to

building on these achievements with a catalyst-rich fourth quarter and 2021.

THIRD QUARTER 2020 & RECENT HIGHLIGHTS

KEY UPCOMING MILESTONES

Rare Genetic Diseases

Hematologic Malignancies and Solid Tumors

UPCOMING INVESTOR EVENTS

THIRD QUARTER 2020 FINANCIAL RESULTS

Revenue: Total revenue for the third quarter of 2020 was $34.7 million, which includes $31.7 million of net product revenue from sales of

TIBSOVO , $2.3 million in collaboration revenue and $0.7 million in royalty revenue from net global sales of IDHIFA under

our collaboration agreement with Celgene, now a wholly owned subsidiary of Bristol Myers Squibb. This compares to revenue of $26.0 million for the third quarter of 2019. Total revenue increased 33% from the same period last year, driven by an

82% increase in TIBSOVO net product revenue and offset by a decrease in collaboration revenue due to completion of the research and development services performance obligation with Celgene in

the second quarter, as well as an adjustment in sales reserves taken in the third quarter by Bristol Myers Squibb.

Cost of Sales: Cost of sales were $0.6 million for the third quarter of 2020 compared to

$0.4 million for the third quarter of 2019.

Research and Development (R&D) Expenses: R&D expenses were $89.6 million for the

third quarter of 2020 compared to $101.7 million for the third quarter of 2019. The decrease in R&D expense was primarily attributable to a decrease in TIBSOVO clinical development

costs, including winding down the ClarIDHy Phase 3 study.

Selling, General and Administrative (SG&A) Expenses: SG&A expenses were

$34.8 million for the third quarter of 2020 compared to $33.0 million for the third quarter of 2019. The increase in SG&A expense was primarily attributable to increased workforce expenses, offset by a decrease in external spending due

to COVID-19 and cost savings initiatives.

Net Loss: Net loss was $99.0 million for the third quarter

of 2020 compared to $106.2 million for the third quarter of 2019.

Cash Position and Guidance: Cash, cash equivalents and marketable

securities as of September 30, 2020 were $722.4 million, compared to $540.5 million as of September 30, 2019. The company expects that its cash, cash equivalents and marketable securities as of September 30, 2020, together

with anticipated product revenue, anticipated interest income and anticipated expense reimbursements under our collaboration and license agreements, but excluding any additional program-specific milestone payments, will enable the company to fund

its anticipated operating expenses and capital expenditure requirements to the end of 2022.

CONFERENCE CALL INFORMATION

Agios will host a conference call and live webcast with slides today at 8:00 a.m. ET to discuss its third quarter 2020 financial results and recent business

activities. To participate in the conference call, please dial 1-877-377-7098 (domestic) or 1-631-291-4547 (international) and refer to conference ID 7578909. The live webcast can be accessed under Events & Presentations in the Investors

section of the company s website at www.agios.com. The archived webcast will be available on the company s website beginning approximately two hours after the event.

About the Agios/Celgene Collaboration In 2010, Agios and Celgene Corporation, now a wholly owned subsidiary of Bristol Myers Squibb, entered

into a collaboration agreement focused on cancer metabolism. Under the terms of the agreement, Celgene has worldwide development and commercialization rights for IDHIFA (enasidenib).

Celgene and Agios are currently co-commercializing IDHIFA in the U.S., and Agios continues to conduct certain clinical development activities

within the IDHIFA development program. Agios is eligible to receive a $25 million payment upon achievement of a specified

ex-U.S. commercial milestone event, as well as reimbursement for costs incurred for its co-commercialization efforts and development activities.

Agios is focused on discovering and developing novel investigational medicines to treat malignant hematology, solid tumors and rare genetic diseases through

scientific leadership in the field of cellular metabolism. In addition to an active research and discovery pipeline across these three therapeutic areas, Agios has two approved oncology precision medicines and multiple

first-in-class investigational therapies in clinical and/or preclinical development. For more information, please visit the company s website at

Cautionary Note Regarding Forward-Looking Statements

This press release contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Such forward-looking

statements include those regarding Agios plans, strategies and expectations for its and its collaborator s preclinical, clinical and commercial advancement of its drug development programs including TIBSOVO (ivosidenib tablets), IDHIFA (enasidenib), mitapivat, and AG-946; the potential benefits of

Agios product candidates; its key milestones and guidance for 2020; its plans regarding future data presentations; its financial guidance regarding the period in which it will have capital available to fund its operations; and the potential

benefits of its strategic plans and focus. The words anticipate, expect, goal, hope, milestone, plan, potential, possible, strategy,

will, vision, and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Such statements are subject to numerous important

factors, risks and uncertainties that may cause actual events or results to differ materially from Agios current expectations and beliefs. For example, there can be no guarantee that any product candidate Agios or its collaborators is

developing will successfully commence or complete necessary preclinical and clinical development phases, or that development of any of Agios product candidates will successfully continue. There can be no guarantee that any positive

developments in Agios business will result in stock price appreciation. Management s expectations and, therefore, any forward-looking statements in this press release could also be affected by risks and uncertainties relating to a number

of other important factors, including, without limitation: risks and uncertainties related to the impact of the COVID-19 pandemic to Agios business, operations, strategy, goals and anticipated

milestones, including its ongoing and planned research activities, ability to conduct ongoing and planned clinical trials, clinical supply of current or future drug candidates, commercial supply of current or future approved products, and launching,

marketing and selling current or future approved products; Agios results of clinical trials and preclinical studies, including subsequent analysis of existing data and new data received from ongoing and future studies; the content and timing

of decisions made by the U.S. FDA, the EMA or other regulatory authorities, investigational review boards at clinical trial sites and publication review bodies; Agios ability to obtain and maintain requisite regulatory approvals and

to enroll patients in its planned clinical trials; unplanned cash requirements and expenditures; competitive factors; Agios ability to obtain, maintain and enforce patent and other intellectual property protection for any product candidates it

is developing; Agios ability to maintain key collaborations; and general economic and market conditions. These and other risks are described in greater detail under the caption Risk Factors included in Agios public filings

with the Securities and Exchange Commission. Any forward-looking statements contained in this press release speak only as of

the date hereof, and Agios expressly disclaims any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by

Consolidated Balance Sheet Data

Consolidated Statements of Operations Data

(in thousands, except share and per share data)

Director, Investor Relations

Jessica Rennekamp, 857-209-3286

Associate Director, Corporate Communications