Provider Briefing: The Pegasys Shortage in 2026

The ongoing shortage of Pegasys (Peginterferon Alfa-2a) continues to present significant challenges for providers across hepatology, hematology, and infectious disease. This briefing provides the current state of supply, prescribing implications, and actionable guidance for managing affected patients.

Shortage Timeline

The Pegasys shortage has evolved through several phases:

• 2023–2024: Roche/Genentech divested Pegasys to pharma& GmbH, a European pharmaceutical company. Manufacturing site transitions began.
• October 2024: pharma& proactively notified the US FDA of potential supply constraints as demand outpaced production capacity at existing facilities.
• Late 2024: ASHP officially listed Peginterferon Alfa-2a as being in shortage. Supply through specialty distributor Summit SD became limited.
• April 2025: EMA approved pharma&'s new API manufacturing site (Loba biotech GmbH) for European supply.
• 2025–2026: US FDA review of the new manufacturing site remains ongoing. Supply continues to be constrained, with allocations limiting order quantities.

Prescribing Implications

The shortage has distinct implications depending on the clinical indication:

Myeloproliferative Neoplasms (PV/ET)

Pegasys has been one of the most widely prescribed interferons for polycythemia vera and essential thrombocythemia in the US, despite being used off-label for these conditions. The shortage has been most impactful for MPN patients because:

• These patients often require long-term or indefinite therapy
• Treatment interruptions can lead to loss of hematologic and molecular response
• Many patients were dose-optimized on Pegasys and transitioning to an alternative requires careful monitoring

The NCCN Myeloproliferative Neoplasms Guidelines (Version 1.2025) now explicitly address the shortage, recommending BESREMi (Ropeginterferon Alfa-2b-njft) as a substitute for PV patients who cannot access Pegasys. Published transition guidance (Annals of Hematology, 2025) provides dosing conversion recommendations for switching patients from Pegasys to BESREMi.

Chronic Hepatitis C

For the majority of CHC patients, interferon-free direct-acting antiviral (DAA) regimens are the standard of care and represent a clear alternative. The Pegasys shortage provides an additional impetus to transition any remaining interferon-based hepatitis C patients to DAA therapy (Harvoni, Epclusa, Mavyret, or other approved regimens).

The limited remaining use case for Pegasys in CHC is patients with contraindications to all available DAAs — an exceedingly rare clinical scenario.

Chronic Hepatitis B

Pegasys remains one of few FDA-approved interferon options for CHB, particularly for patients pursuing a finite treatment course (typically 48 weeks) with the goal of HBsAg seroconversion. Alternatives include:

• Oral nucleos(t)ide analogues: Entecavir, Tenofovir disoproxil fumarate, Tenofovir alafenamide — effective viral suppressants but typically require indefinite treatment
• PegIntron (Peginterferon Alfa-2b): Another pegylated interferon that may be available in limited supply, though it also faces supply constraints

For CHB patients on active Pegasys therapy, the priority should be ensuring no treatment gaps, as interruptions can lead to hepatitis flares.

Current Availability Picture

As of early 2026:

• Summit SD remains the primary specialty distributor for Pegasys in the US, with limited allocation-based supply
• 180 mcg/mL vials and 180 mcg/0.5 mL prefilled syringes are the presentations currently available in limited quantities
• Autoinjectors (135 mcg and 180 mcg) may have more constrained availability
• pharma& has indicated that supply is expected to improve as new manufacturing capacity comes online, but no firm timeline has been provided for the US market

Cost and Access Considerations

The financial burden of Pegasys can be substantial for patients:

• Cash price: ~$1,095–$1,200 per vial/syringe (~$4,300–$4,800/month)
• Insurance: Typically covered under specialty pharmacy or medical benefit with prior authorization; specialty tier copays apply
• Medicare Part D: The $2,000 annual out-of-pocket cap (effective 2025) reduces patient exposure significantly
• Patient assistance: pharma& PAP available at 855-443-7028; additional resources through NeedyMeds and RxAssist

For patients facing access barriers, Medfinder for Providers offers real-time pharmacy stock tracking to help locate Pegasys availability.

Tools and Resources for Providers

• Medfinder for Providers: Real-time pharmacy stock search — locate Pegasys availability for your patients
• ASHP Drug Shortage Database: Official shortage tracking and updates
• pharma& Patient Line: 855-443-7028 — supply information and patient assistance
• NCCN Guidelines (MPN, v1.2025): Pegasys-to-BESREMi transition recommendations
• Annals of Hematology (2025): Published dosing guidance for transitioning PV/ET patients from Pegasys to Ropeginterferon Alfa-2b

Looking Ahead

Several developments may improve the situation over the next 6–12 months:

• US FDA approval of pharma&'s new manufacturing site would increase available supply for the US market
• Growing BESREMi adoption in hematology may relieve some demand pressure on Pegasys for MPN indications
• Biosimilar development: While no biosimilar Peginterferon Alfa-2a is imminent in the US, patents have expired in major markets, potentially opening the door for future competition

Final Thoughts

The Pegasys shortage requires a proactive, patient-specific approach. For MPN patients, BESREMi offers a viable FDA-approved alternative. For hepatitis C patients, DAA therapy should be standard. For hepatitis B patients, ensuring treatment continuity is paramount.

Use Medfinder for Providers to track availability, stay connected with specialty distributors, and communicate transparently with patients about the situation. For a patient-facing version of this update, share: Pegasys shortage update for patients.