Enanta Pharmaceuticals, Inc. is a biotechnology company, which engages in the discovery and development of small molecule drugs for the treatment of viral infections and liver diseases. It produces clinical candidates which targets respiratory syncytial virus (RSV), hepatitis B virus (HBV), and non-alcoholic steatohepatitis (NASH) diseases. The firm also conducts research in human metapneumovirus (hMPV) and SARS-CoV-2 (COVID-19). The company was founded by Peter O. Kliem Martin Karplus, James Hogle, Gerard Wagner, Peter M. Howley, and Gregory L. Verdine in 1995 and is headquartered in Watertown, MA.
Clinical Trials
54
7 active
Approvals
0
Total approvals
Agencies
0
Regulatory bodies
Founded
N/A
Active, not recruiting
7
13.0%
Completed
40
74.1%
Recruiting
2
3.7%
Terminated
4
7.4%
Unknown
1
1.9%
No approval data available
- Enanta's zelicapavir demonstrated clinically meaningful improvement in RSV symptom resolution with a 6.7-day benefit for high-risk patients in Phase 2b trials, leading to Phase 3 enabling activities. - The company announced its third immunology program targeting MRGPRX2, a mast cell receptor, with prototype inhibitors showing nanomolar potency and potential for treating chronic inflammatory diseases. - EDP-978, an oral KIT inhibitor for chronic spontaneous urticaria, is on track for IND filing in Q1 2026, while EPS-3903, a STAT6 inhibitor for atopic dermatitis, targets IND submission in H2 2026.
- The 2014 hepatitis C market battle between AbbVie and Gilead Sciences saw dramatic price reductions from $80,000 to $20,000 per treatment course when viable competition emerged. - AbbVie's Viekira Pak launched at $83,319 with a 12% discount to Gilead's Harvoni, triggering Express Scripts to drop Harvoni coverage in favor of the cheaper alternative. - Current GLP-1 obesity drug competition between Novo Nordisk and Eli Lilly mirrors this pricing dynamic, with both companies announcing $350 monthly pricing at the White House. - Unlike hepatitis C's one-time curative treatment, obesity medications require lifelong maintenance dosing, creating different budget impact calculations for healthcare systems.
- Enanta Pharmaceuticals' EDP-323, a first-in-class oral L-protein inhibitor, achieved 85-87% reduction in RSV viral load and 66-78% reduction in symptoms compared to placebo in a Phase IIa human challenge study. - The antiviral effect was evident as early as 12 hours after the first dose, marking one of the fastest onsets of activity observed in the RSV antiviral space. - EDP-323 demonstrated a favorable safety profile with treatment-emergent adverse events occurring at similar rates to placebo (26.6% vs 27.7%), supporting advancement to Phase IIb trials. - The drug showed potential for both therapeutic and preventive utility, with 0% infection rate in post-exposure prophylaxis analysis compared to 26% with placebo.
- Enanta Pharmaceuticals completed an upsized public offering of 6.5 million shares at $10.00 per share, raising $65 million in gross proceeds to fund its clinical programs. - The biotechnology company focuses on small molecule drug discovery for virology and immunology, with current clinical programs targeting respiratory syncytial virus (RSV). - Enanta's immunology pipeline aims to develop treatments for inflammatory diseases by targeting key drivers of the type 2 immune response, including KIT and STAT6 inhibition. - The company previously discovered glecaprevir, a protease inhibitor that is part of leading hepatitis C virus treatment regimens sold by AbbVie as MAVYRET/MAVIRET.
- Enanta Pharmaceuticals filed a patent infringement lawsuit against Pfizer in the EU's Unified Patent Court on August 20, 2025, alleging that Paxlovid violates European Patent No. EP 4 051 265 for coronavirus protease inhibitors. - The lawsuit represents a strategic pivot after Enanta's corresponding U.S. patent was invalidated in December 2024, with the company seeking damages rather than injunctive relief to keep Paxlovid available to patients. - With $204.1 million in cash reserves and Paxlovid generating over $26 billion globally since 2021, the case could significantly impact both companies' financial positions and reshape IP enforcement strategies in the pharmaceutical sector.
- XtalPi has signed a Letter of Intent with DoveTree LLC, founded by Harvard Professor Gregory Verdine, for a collaboration worth $100 million upfront plus potential milestone payments exceeding $10 billion. - The partnership will leverage XtalPi's AI and robotics-driven platform to discover small molecule and antibody drug candidates targeting oncology, autoimmune disorders, and neurological diseases. - Professor Verdine brings extensive drug development expertise, having co-founded over ten biotechnology companies and spearheaded three FDA-approved therapeutics including romidepsin, paritaprevir, and glecaprevir. - DoveTree will obtain exclusive global development and commercialization rights to resulting therapeutics, while XtalPi is eligible for tiered royalties on net product sales.
- The U.S. FDA approved an expanded indication for AbbVie's MAVYRET (glecaprevir/pibrentasvir), making it the first and only oral eight-week pangenotypic treatment approved for people with acute hepatitis C virus infection. - The approval was supported by Phase 3 trial data showing a 96% cure rate in 286 treatment-naïve adult patients with acute HCV infection treated for eight weeks. - MAVYRET received FDA Breakthrough Therapy Designation for acute HCV treatment, designed to expedite development of medicines that demonstrate substantial improvement over existing therapies. - The expanded indication supports global clinical guidelines for universal HCV treatment and public health goals to eliminate hepatitis C as a public health problem by 2030.
- Enanta Pharmaceuticals has filed patent infringement lawsuits against Pfizer in both US and EU courts, claiming Paxlovid infringes its patents covering coronavirus 3CL protease inhibitors. - The biotech company seeks damages from Pfizer's expected $22 billion in Paxlovid sales this year, while stating it won't seek an injunction that would impede the drug's availability to patients. - Enanta has its own COVID-19 drug candidate EDP-235 targeting the same 3CL protease in phase 1 trials with FDA fast-track designation, highlighting the competitive landscape in coronavirus therapeutics.
- Enanta Pharmaceuticals will showcase data from its Phase 2 study of zelicapavir in RSV-infected children at the ESPID 2025 meeting, including new findings on PK/PD and viral clearance rates. - The company will also present results from its Phase 2a human challenge study of EDP-323, a first-in-class RSV polymerase inhibitor, at ESCMID Global 2025, featuring new data on respiratory mucus reduction. - Both oral antivirals represent significant advances in RSV treatment development, targeting different viral proteins and demonstrating promising efficacy in their respective clinical trials.
- Enanta Pharmaceuticals' zelicapavir achieved a significant 0.7 log reduction in peak viral load on Day 9 in a Phase 2 trial for pediatric RSV patients. - The RSVPEDs study included both hospitalized and non-hospitalized children aged 28 days to 36 months, with consistent results across age groups. - H.C. Wainwright revised its model for Enanta, reducing the price target to $18.00 while maintaining a Buy rating based on the RSVPEDs study data. - Enanta is appealing a court decision that ruled against them in a patent infringement lawsuit with Pfizer over Paxlovid, impacting the company's financial outlook.
