Enanta Pharmaceuticals Reports Financial Results for its Fiscal First Quarter and Three Months Ended

Enanta Pharmaceuticals Reports Financial Results for its Fiscal First Quarter and Three Months Ended December 31, 2019

Webcast and Conference Call Today at 4:30 p.m. ET

WATERTOWN, Mass., February 6, 2020 Enanta Pharmaceuticals, Inc. (NASDAQ:ENTA), a research and development-focused

biotechnology company dedicated to creating small molecule drugs for viral infections and liver diseases, today reported financial results for its fiscal first quarter ended December 31, 2019.

We achieved the first of our 2020 milestones with today s announcement of positive data in healthy subjects with

EDP-514, our core inhibitor for HBV. EDP-514 was found to be safe and well-tolerated in healthy adults, with a pharmacokinetic profile that demonstrated good blood

levels to support once daily dosing. These results support further clinical evaluation, so we have initiated part 2 of the study in nuc-suppressed chronic HBV patients, stated Jay R. Luly, Enanta

President and CEO. We look forward to reporting further clinical results and updates from our other wholly-owned clinical programs in RSV, NASH and PBC in 2020.

Fiscal First Quarter Ended December 31, 2019 Financial Results

Total revenue for the three months ended December 31, 2019 was $52.6 million and consisted entirely of royalty revenue from worldwide net sales of

AbbVie s hepatitis C virus (HCV) regimens. For the three months ended December 31, 2018, total royalty revenue was $69.9 million.

and development expenses totaled $32.8 million for the three months ended December 31, 2019, compared to $34.9 million for the three months ended December 31, 2018. The decrease was primarily due to the timing of clinical trial

costs associated with the progression of Enanta s wholly owned clinical programs in respiratory syncytial virus (RSV), non-alcoholic steatohepatitis (NASH), primary biliary cholangitis (PBC), and

hepatitis B virus (HBV).

General and administrative expenses totaled $6.9 million for the three months ended December 31,

2019 compared to $7.2 million for the three months ended December 31, 2018.

Enanta recorded income tax expense of $1.5 million for the

three months ended December 31, 2019 compared to an income tax expense of $3.7 million for the same period in 2018. Enanta s effective tax rate for the December 31, 2019 quarter was approximately 10 percent compared to

approximately 12.5 percent for the corresponding period in 2018. The decrease quarter over quarter was due primarily to increased research and development tax credits and a federal income tax benefit from foreign-derived royalty income.

Net income for the three months ended December 31, 2019 was $13.4 million, or $0.65 per diluted common share, compared to net income of

$26.0 million, or $1.25 per diluted common share, for the corresponding period in 2018.

Enanta s cash, cash equivalents and short-term and

long-term marketable securities totaled $414.7 million at December 31, 2019. This compares to a total of $400.2 million at September 30, 2019. Enanta expects that its current cash, cash equivalents and marketable securities, as

well as its continuing royalty revenue, will be sufficient to meet the anticipated cash requirements of its existing business and development programs for the foreseeable future.

Phase 1 data for core inhibitor EDP-514 for HBV

The Phase 1 randomized, double-blind, placebo-controlled, first-in-human study

of EDP-514 was conducted to evaluate the safety, tolerability, and pharmacokinetics (PK) of single- and multiple- (14 days) ascending doses of EDP-514 in healthy

Overall, EDP-514 in healthy subjects dosed for up to 14 days was well tolerated with a favorable safety

profile; treatment emergent adverse events were infrequent and mild in intensity; no one discontinued EDP-514 due to adverse events; and there were no significant individual lab data findings or pattern of lab

abnormalities. Additionally, the pharmacokinetic (blood level) profile was fully supportive of once daily dosing.

Following these results, which support

further clinical evaluation of EDP-514 in HBV patients, Enanta has initiated a study in patients with chronic HBV infection that is being suppressed with

nucleos(t)ide-reverse-transcriptase treatment (nuc-suppressed patients). A further study is planned in patients with chronic HBV infection who are not on therapy and

have high levels of virus in their blood (viremic patients).

Further details of results from this Phase 1a study will be presented at the International

Liver Congress , April 15-20, 2020.

Upcoming Events and Presentations

Conference Call and Webcast Information

a conference call and webcast today at 4:30 p.m. ET. To participate in the live conference call, please dial (855) 840-0595 in the U.S. or (518) 444-4814 for

international callers. A replay of the conference call will be available starting at approximately 7:30 p.m. ET on February 6, 2020, through 11:59 p.m. ET on February 8, 2020 by dialing (855)

859-2056 from the U.S. or (404) 537-3406 for international callers. The passcode for both the live call and the replay is 3972249. A live audio webcast of the call and

replay can be accessed by visiting the Events and Presentation section on the Investors page of Enanta s website at www.enanta.com.

Enanta is using its robust,

chemistry-driven approach and drug discovery capabilities to become a leader in the discovery and development of small molecule drugs for the treatment of viral infections and liver diseases. Enanta s research and development efforts have

produced clinical candidates for the following disease targets: respiratory syncytial virus (RSV), non-alcoholic steatohepatitis (NASH)/ primary biliary cholangitis (PBC), and hepatitis B virus (HBV).

Enanta s research and development activities are funded by royalties from HCV products developed under its collaboration with AbbVie. Glecaprevir, a protease inhibitor discovered by Enanta, is now sold by AbbVie in numerous countries as part of

its leading treatment for chronic hepatitis C virus (HCV) infection sold under the tradenames MAVYRET (U.S.) and MAVIRET (ex-U.S.) (glecaprevir/pibrentasvir). Please visit www.enanta.com for more information.

FORWARD LOOKING STATEMENTS

This press release contains forward-looking statements, including statements with respect to the prospects for advancement of Enanta s clinical programs

in RSV, NASH/PBC and HBV, as well as Enanta s prospects for future royalty revenue from sales of AbbVie s MAVYRET /MAVIRET

regimen for HCV. Statements that are not historical facts are based on management s current expectations, estimates, forecasts and projections about Enanta s business and the industry in which it operates and management s beliefs and

assumptions. The statements contained in this release are not guarantees of future performance and involve certain risks, uncertainties and assumptions, which are difficult to predict. Therefore, actual outcomes and results may differ materially

from what is expressed in such forward-looking statements. Important factors and risks that may affect actual results include: the dependence of Enanta s revenues in the short-term upon the continued success of AbbVie s sales of its

MAVYRET /MAVIRET HCV regimen; the impact of development, regulatory and marketing efforts of others with respect to competitive

treatments for RSV, NASH, PBC and HBV; treatment rates, competitive pricing, and reimbursement rate actions affecting

MAVYRET /MAVIRET compared to competitive HCV products on the market; the discovery and development risks of Enanta s programs in

RSV, NASH, PBC, and HBV; the competitive impact of development, regulatory and marketing efforts of others in those disease areas; Enanta s lack of clinical development experience; Enanta s need to attract and retain senior management and

key research and development personnel; Enanta s need to obtain and maintain patent protection for its product candidates and avoid potential infringement of the intellectual property rights of others; and other risk factors described or

referred to in Risk Factors in Enanta s most recent Form 10-K for the year ended, 2019, and other periodic reports filed more recently with the Securities and Exchange Commission. Enanta

cautions investors not to place undue reliance on the forward-looking statements contained in this release. These statements speak only as of the date of this release, and Enanta undertakes no obligation to update or revise these statements, except

as may be required by law.

MacDougall Biomedical Communications

ENANTA PHARMACEUTICALS, INC.

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