On May 22, 2026, the FDA granted accelerated approval to Gilead Sciences' Hepcludex (bulevirtide-gmod) 8.5 mg for the treatment of adults living with chronic hepatitis delta virus (HDV) infection without cirrhosis or with compensated cirrhosis. Hepcludex is the first and only FDA-approved treatment for HDV in the United States — addressing a disease that has had no approved therapy despite being the most severe form of viral hepatitis.
This coverage guide is for hepatology access teams, specialty pharmacy professionals, payer strategists, and rare-disease program managers who need to understand Hepcludex's regulatory status, clinical evidence, distribution pathway, and patient access logistics.
What Hepcludex is and how it works
Hepcludex (bulevirtide-gmod) is a first-in-class viral entry inhibitor. It blocks the sodium taurocholate co-transporting polypeptide (NTCP) receptor on hepatocytes, preventing both HDV and hepatitis B virus (HBV) from entering liver cells. This mechanism targets a key step in the viral lifecycle distinct from existing HBV therapies.
Key parameters:
| Parameter | Hepcludex (bulevirtide-gmod) |
|---|---|
| Generic | Bulevirtide-gmod |
| Brand | Hepcludex |
| Class | Viral entry inhibitor (first-in-class) |
| Route | Subcutaneous injection |
| Dose | 8.5 mg once daily (per FDA label); earlier European studies used 2 mg and 10 mg doses |
| Manufacturer | Gilead Sciences |
| Approval date | May 22, 2026 |
| Approval pathway | Accelerated approval |
| Designations | Breakthrough Therapy, Orphan Drug, Priority Review |
Chronic HDV is a co-infection that occurs only in individuals who already have hepatitis B. It affects approximately 40,000 people in the United States and causes faster progression to liver fibrosis, cirrhosis, hepatic decompensation, liver cancer, and death compared with HBV alone.
Clinical evidence: MYR301
The FDA's accelerated approval was based on data from the pivotal Phase 3 MYR301 trial (NCT03852719), a multicenter, randomized, open-label study. MYR301 enrolled 150 adults with chronic HDV who were randomized to immediate treatment with bulevirtide for 144 weeks or delayed treatment (observation for 48 weeks followed by treatment for 96 weeks).
Primary endpoint at Week 48:
- Combined response (undetectable HDV RNA or ≥2 log10 IU/mL decline plus ALT normalization): 48% in the immediate-treatment group vs. 2% in the delayed-treatment group
- The difference was statistically significant
Long-term data:
- Treatment for up to 144 weeks demonstrated sustained efficacy and was generally well tolerated
- At Week 96, the proportion achieving combined response was 56% (bulevirtide 2 mg arm)
- 36% of patients who achieved undetectable HDV RNA at end of treatment maintained virologic suppression for nearly two years after stopping treatment
- Among participants with sustained undetectability for one year post-treatment, no relapses occurred in the second year of follow-up
The MYR301 results were published in the New England Journal of Medicine (Wedemeyer et al., NEJM 2023) with final post-treatment follow-up data presented at EASL 2025.
Accelerated approval considerations
Hepcludex received accelerated approval based on reductions in HDV RNA and normalization of ALT — surrogate endpoints reasonably likely to predict clinical benefit. Importantly:
- Improvement in disease-related clinical outcomes has not been established
- Continued approval may be contingent upon verification of clinical benefit in a confirmatory trial
- Gilead is conducting ongoing follow-up studies
This has direct access implications: payers may impose reauthorization requirements tied to virologic response, and some may request clinical outcome data before granting unrestricted coverage.
Specialty pharmacy distribution
On May 26, 2026, Orsini Healthcare announced it is the contracted specialty pharmacy for Hepcludex. Orsini is a leader in rare disease pharmacy solutions with URAC Rare Disease Pharmacy Center of Excellence designation and ACHC Distinction in Rare Diseases and Orphan Drugs.
Distribution logistics:
- Hepcludex will be dispensed through Orsini's rare disease pharmacy network
- Subcutaneous injection requires patient or caregiver training
- Home infusion services may be available through Orsini's integrated care model
- Therapy care teams provide personalized patient support
Access teams should note that limited distribution networks (single specialty pharmacy) are common for rare disease launches and may require specific enrollment steps.
Payer coverage and prior authorization considerations
Because Hepcludex is the first approved treatment for HDV, payers will need to build new coverage policies from scratch. Key factors that will shape PA criteria:
Likely prior authorization requirements:
- Confirmed chronic HDV infection (HDV RNA positive) with documented hepatitis B surface antigen (HBsAg) positivity
- Absence of decompensated cirrhosis (per FDA label restriction to no cirrhosis or compensated cirrhosis)
- Prescribed by or in consultation with a hepatologist or infectious disease specialist
- Baseline ALT and HDV RNA levels documented
Reauthorization criteria (anticipated):
- Continued HDV RNA suppression or decline from baseline
- ALT improvement or normalization
- Tolerance of therapy without dose-limiting adverse events
Medicare and Medicaid considerations:
- Hepcludex carries Orphan Drug designation, which provides certain Medicaid rebate protections
- Medicare Part D plans will need to add Hepcludex to formularies; expect specialty tier placement
- State Medicaid programs vary in their coverage of accelerated-approval drugs with unconfirmed clinical benefit
Patient assistance and affordability
Gilead has announced that its Gilead Support Path program will provide information and resources to help patients diagnosed with chronic HBV, HDV, HCV, and PBC understand coverage and financial options for prescribed Gilead treatments. This is the established patient support infrastructure through which Hepcludex access will be managed.
Expected support pathways:
- Copay assistance programs for commercially insured patients
- Patient assistance (free drug) for uninsured or underinsured patients
- Specialty-level copay or coinsurance given the Orphan Drug designation and rare disease population
- Support Path coordinators to assist with benefits investigation and prior authorization support
Access teams should contact Gilead Support Path directly for Hepcludex-specific enrollment forms and coverage investigation.
European context
Hepcludex 2 mg received conditional marketing authorization from the European Commission in July 2020 for chronic HDV with compensated liver disease, and full approval in July 2023. The European experience provides useful real-world data on long-term use and patient management. The FDA-approved 8.5 mg dose is higher than the European 2 mg dose, reflecting the US regulatory review of the full MYR301 dose-ranging data.
What access teams should monitor
- Official US launch pricing. Gilead has not disclosed WAC pricing. Monitor DailyMed and Gilead press releases for label and pricing details.
- Confirmatory trial enrollment. Accelerated approval requires a confirmatory trial. Track ClinicalTrials.gov for ongoing and new bulevirtide studies.
- Payer policy development. Major PBMs (CVS Caremark, Express Scripts, OptumRx) and commercial payers will issue coverage determinations in the coming months.
- Companion diagnostic access. HDV RNA testing availability and turnaround time will affect time-to-treatment. Work with lab partners to ensure HDV testing is accessible.
- Specialty pharmacy enrollment. Initiate Orsini enrollment early to avoid treatment delays.
Sources
- FDA press release: "FDA Approves First Treatment for Chronic Hepatitis Delta Virus (HDV) Infection": https://www.fda.gov/news-events/press-announcements/fda-approves-first-treatment-chronic-hepatitis-delta-virus-hdv-infection
- Gilead Sciences press release: "FDA Grants Accelerated Approval to Gilead's Hepcludex (bulevirtide-gmod)": https://www.gilead.com/news/news-details/2026/fda-grants-accelerated-approval-to-gileads-hepcludex-bulevirtide-gmod-the-first-and-only-approved-treatment-for-chronic-hepatitis-delta-virus-hdv
- ClinicalTrials.gov MYR301 (NCT03852719): https://clinicaltrials.gov/study/NCT03852719
- Wedemeyer H et al. "A Phase 3, Randomized Trial of Bulevirtide in Chronic Hepatitis D." N Engl J Med. 2023;389(1):22-32: https://pubmed.ncbi.nlm.nih.gov/37386278/
- Orsini press release: "Orsini to Serve as Contracted Specialty Pharmacy for Gilead's Hepcludex": https://www.prnewswire.com/news-releases/orsini-to-serve-as-contracted-specialty-pharmacy-for-gileads-hepcludex-bulevirtidegmod-302780820.html
- Gilead final MYR301 data release: https://www.gilead.com/news/news-details/2025/final-data-from-the-phase-3-myr301-study-demonstrated-longer-treatment-with-bulevirtide-was-associated-with-sustaining-undetectability-after-stopping-treatment
- PubMed: "144 Weeks of bulevirtide monotherapy for chronic hepatitis D: Final and posttreatment results from a Phase 3 randomized trial": https://pubmed.ncbi.nlm.nih.gov/41966308
- CVS Health: "What's next in treatment: four drugs that could change care this spring": https://www.cvshealth.com/news/pbm/whats-next-in-treatment-four-drugs-that-could-change-care-this-spring.html
