Acceleron Pharma Inc.
May 8, 2017

Acceleron Pharma Reports First Quarter 2017 Operational and Financial Results

- Luspatercept MEDALIST and BELIEVE Phase 3 trials expected to complete enrollment in Q2 2017 -

- Presented results from ongoing Phase 2 trial with luspatercept at the 14th International Symposium on MDS -

- Announced plans to initiate luspatercept Phase 3 trial in first-line, lower-risk MDS in early 2018 -

- Announced plans to initiate ACE-083 Phase 2 study in Charcot-Marie-Tooth disease -

- Maintained strong balance sheet with $213.2 million in cash, cash equivalents and investments to fund projected operating requirements into the second half of 2019 -

CAMBRIDGE, Mass.--(BUSINESS WIRE)-- Acceleron Pharma Inc. (NASDAQ:XLRN), a clinical stage biopharmaceutical company focused on the discovery, development and commercialization of innovative therapeutics to treat serious and rare diseases, today provided a corporate update and reported financial results for the first quarter ended March 31, 2017.

"In the first quarter, we made significant progress across our entire pipeline. Our luspatercept program in MDS and beta-thalassemia continues to build momentum, as we look to complete enrollment of the MEDALIST and BELIEVE Phase 3 studies ahead of schedule, and expand into additional patient populations where there are limited treatment options, including first-line, lower-risk MDS and myelofibrosis," said Habib Dable, President and Chief Executive Officer of Acceleron. "As we continue to explore further expansion opportunities for luspatercept, we are also preparing to expand our wholly-owned pipeline into a second neuromuscular disease, with the expected initiation by mid-year of a Phase 2 study with ACE-083 in patients with Charcot-Marie-Tooth disease."

DEVELOPMENT PROGRAM HIGHLIGHTS

Hematology

Luspatercept in myelodysplastic syndromes (MDS)

Luspatercept is being developed to treat anemia and reduce or eliminate the need for red blood cell transfusions in patients with MDS, a rare disorder in which bone marrow fails to produce enough healthy blood cells. Luspatercept is being developed as part of the global collaboration between Acceleron and Celgene.

Luspatercept in beta-thalassemia

Luspatercept is designed to treat severe, chronic anemia and reduce RBC transfusion-dependence in adults with beta-thalassemia, a rare genetic disorder that reduces the production of hemoglobin. Luspatercept is being developed as part of the global collaboration between Acceleron and Celgene.

Neuromuscular Disease

ACE-083 in facioscapulohumeral muscular dystrophy (FSHD) and Charcot-Marie-Tooth (CMT) disease

ACE-083 is designed to increase muscle mass and strength in target muscles for diseases that cause debilitating focal muscle loss.

Preclinical Research

Acceleron continues its research on several molecules targeting musculoskeletal diseases, fibrotic disorders and other serious diseases.

NEWSFLOW AND CATALYSTS

Luspatercept

ACE-083

Dalantercept

ACE-2494

Corporate

Financial Results

Conference Call and Webcast

The Company will host a live conference call and webcast to discuss its first quarter 2017 financial results and provide a corporate update on May 8, 2017, at 8:00 a.m. EDT. Participants can access the live conference call by dialing 877-312-5848 (domestic) or 253-237-1155 (international) and refer to the "Acceleron Earnings Call."

The live webcast can be accessed on the Investors page of the Company's website at www.acceleronpharma.com.

A replay of the webcast will be available approximately two hours after the event on the Company's website.

About Acceleron

Acceleron is a clinical stage biopharmaceutical company focused on the discovery, development and commercialization of innovative therapeutics to treat serious and rare diseases. Its pioneering research platform leverages the powerful biology behind the body's ability to rebuild and repair its own cells and tissues. This approach to drug discovery has generated four therapeutic candidates that are currently in clinical trials. The Company's lead therapeutic candidate, luspatercept, is being evaluated in Phase 3 studies for the treatment of the hematologic diseases myelodysplastic syndromes and beta-thalassemia under a global partnership with Celgene Corp. Acceleron is also advancing clinical programs in the fields of oncology and neuromuscular diseases and has a comprehensive preclinical research effort targeting fibrotic and other serious diseases.

For more information, please visit www.acceleronpharma.com. Follow Acceleron on Social Media: @AcceleronPharma and LinkedIn.

ACCELERON PHARMA INC.

CONDENSED CONSOLIDATED BALANCE SHEET

(Amounts in thousands)

(unaudited)

       
March 31, 2017   December 31, 2016
Cash and cash equivalents $ 33,157 $ 20,950
Short and long-term investments 180,057 213,432
Other assets 15,915   13,265
Total assets $ 229,129   $ 247,647
 
Deferred revenue $ 4,108 $ 4,245
Warrants to purchase common stock 1,289 1,244
Other liabilities 15,412   16,561
Total liabilities 20,809   22,050
Total stockholders' equity 208,320   225,597
Total liabilities and stockholders' equity $ 229,129   $ 247,647
     

ACCELERON PHARMA INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(Amounts in thousands except per share data)

(unaudited)

 
Three Months Ended March 31,
2017   2016
Revenue:  
Collaboration revenue $ 3,705 $ 18,201
Costs and expenses:
Research and development 21,727 16,246
General and administrative 7,836   5,911  
Total costs and expenses 29,563 22,157
Loss from operations (25,858 ) (3,956 )
Other income, net 457     9,017  
(Loss) income before income taxes $ (25,401 ) $ 5,061
Income tax provision (6 )  
Net (loss) income $ (25,407 ) $ 5,061  
Other comprehensive loss:
Net unrealized holding gains on short-term and long-term investments during the period 25   245  
Comprehensive (loss) income $ (25,382 ) $ 5,306  
 
Net (loss) income per share applicable to common stockholders:
Basic $ (0.66 ) $ 0.14
Diluted $ (0.66 ) $ 0.13
 
Weighted-average number of common shares used in computing net (loss) income per share applicable to common stockholders
Basic 38,404 36,911
Diluted 38,404   38,666  

Cautionary Note on Forward-Looking Statements

This press release contains forward-looking statements about the Company's strategy, future plans and prospects, including statements regarding the development of the Company's compounds, including sotatercept, luspatercept, dalantercept, ACE-083, ACE-2494, the Company's IntelliTrap™ drug discovery platform, and the Company's TGF-beta superfamily program generally, the timeline for clinical development and regulatory approval of the Company's compounds, the expected timing for the reporting of data from ongoing trials, and the structure of the Company's planned or pending clinical trials. The words "anticipate," "believe," "continue," "could," "estimate," "expect," "forecast," "goal", "intend," "may," "plan," "potential," "project," "should," "strategy," "target," "will," "would," and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

Each forward-looking statement is subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied in such statement. Applicable risks and uncertainties include the risks that the Company's cash, cash equivalents and investments will be insufficient to fund operations into the second half of 2019, that preclinical testing of the Company's compounds and data from clinical trials may not be predictive of the results or success of ongoing or later clinical trials, that data may not be available when the Company expects it to be, that the Company or its collaboration partner, Celgene, will be unable to successfully complete the clinical development of the Company's compounds, that the development of the Company's compounds will take longer or cost more than planned, that the Company or Celgene may be delayed in initiating or completing any clinical trials, that the Company's drug discovery activities may not yield drug candidates for which the Company can commence clinical trials at the rate at which the Company currently anticipates or at all, and that the Company's compounds will not receive regulatory approval or become commercially successful products.

Other risks and uncertainties include those identified under the heading "Risk Factors" included in the Company's Annual Report on Form 10-K which was filed with the Securities and Exchange Commission (SEC) on March 1, 2017, and other filings that the Company has made and may make with the SEC in the future. The forward-looking statements contained in this press release reflect the Company's current views with respect to future events, and the Company does not undertake and specifically disclaims any obligation to update any forward-looking statements.

Acceleron Pharma Inc.
Todd James, IRC, 617-649-9393
Senior Director, Investor Relations and Corporate Communications
or
Media:
BMC Communications
Brad Miles, 646-513-3125

Source: Acceleron Pharma Inc.

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