− Framework Ties Payment for GIVLAARI to its Delivery of Patient Outcomes in the Real-World Setting -

− Includes New Approach Designed for Ultra-Rare Diseases that Gives Participating Payers Greater Financial Certainty if Disease Prevalence is Higher Than Anticipated –

- Discussions Underway with Leading Insurers and Agreement in Principle in Place with Harvard Pilgrim -

CAMBRIDGE, Mass.--(BUSINESS WIRE)-- Alnylam Pharmaceuticals, Inc. (Nasdaq: ALNY), the leading RNAi therapeutics company, is announcing today a new and enhanced framework for value-based agreements (VBAs) designed to help patients with acute hepatic porphyria (AHP) – an ultra-rare orphan disease – gain access to GIVLAARI™ (givosiran) injection for subcutaneous use, a first-of-its-kind RNAi therapeutic for the treatment of AHP. Approved today by the U.S. Food and Drug Administration (FDA), GIVLAARI is indicated for the treatment of adults with AHP.

Alnylam is in active discussions with leading payers about VBAs for GIVLAARI and plans to incorporate this new ultra-rare disease framework into these discussions and negotiations. Alnylam has reached an agreement in principle with Harvard Pilgrim covering GIVLAARI.

Under this innovative framework for VBAs, participating government and commercial payers will pay the full value for GIVLAARI only when it delivers patient outcomes in the real-world setting similar to results demonstrated in clinical trials. An additional and newly designed Prevalence-Based Adjustment (PBA) feature will trigger rebates to participating payers if the number of diagnosed patients they cover exceeds current epidemiologic estimates for AHP. There are often uncertainties in diagnosis rates and disease prevalence estimates in ultra-rare diseases, making it challenging for payers to predict the number of patients who will be covered within their plans. This innovative approach offers greater certainty to payers that their overall financial risk will be adjusted if a substantially larger number of patients than currently estimated are identified, diagnosed, and treated with GIVLAARI.

“Patients can sometimes experience lengthy delays waiting for access when a new medicine becomes available, as payers can be challenged to determine both which patients may best respond and the number of potentially undiagnosed patients in their plans,” said Barry Greene, President of Alnylam Pharmaceuticals. “Our proactive approach with VBAs is intended to act as ‘insurance for insurers’ and builds upon our Alnylam Patient Access Philosophy to do everything we can to accelerate patient access to innovative medicines at a sustainable rate to the healthcare system. We are proud of the access achieved in the U.S. for ONPATTRO, and are committed to seeking innovative approaches for patient access with GIVLAARI and each of our approved medicines.”

Currently, the population of AHP patients with diagnosed, active disease in the U.S. and Europe is estimated to be approximately 3,000. Due to the broad, non-specific range of symptoms and comorbidities experienced by AHP patients, the time to diagnosis can be as long as 15 years.

"Harvard Pilgrim applauds Alnylam’s efforts to help us manage plan members’ costs if the number of patients treated exceeds initial forecasts based upon existing prevalence models,” said Michael Sherman, M.D., Chief Medical Officer at Harvard Pilgrim. “This prevalence-based adjustment framework may become a model approach for ultra-rare diseases where few or no therapies have previously existed and where diagnosis rates are uncertain.”

“Express Scripts, Accredo, and Cigna are committed to deliver simpler, more affordable, more predictable ways for patients with rare diseases to receive appropriate care and treatment,” said Steve Miller, M.D., Executive Vice President & Chief Clinical Officer at Express Scripts. “The type of agreement Alnylam is proposing helps ensure people living with acute hepatic porphyria have access to breakthrough medicines and that plans will get value for every dollar they pay for these therapies.”

In the absence of GIVLAARI, an AHP patient can cost $400,000 - $650,000 annually for treatment of attacks, including hospitalization, hemin administration, and other medical interventions. GIVLAARI has been shown to reduce the frequency of attacks thereby providing the potential to reduce or avoid the costs of hospitalization and other interventions. Under Alnylam’s new and enhanced VBA framework, payments will be tied to patient clinical outcomes in the real-world setting mirroring those achieved in the ENVISION study in terms of reduced AHP attacks.

Alnylam’s Patient Access Philosophy The new VBA framework announced today for ultra-rare diseases such as AHP builds upon Alnylam’s Patient Access Philosophy, first released nearly a year ahead of the approval of its first RNAi therapeutic. As part of Alnylam’s Access Philosophy, the Company commits to not increase the price of GIVLAARI by more than the consumer price index for urban consumers (CPI-U), a measure of inflation, in the absence of significant investment associated with a meaningful label expansion. Commercially insured patients are expected to have little-to-no out-of-pocket costs for GIVLAARI. To see Alnylam’s progress as of September 2019, download the report.

Alnylam Assist® Alnylam is deeply committed to helping patients with AHP get access to GIVLAARI. A comprehensive patient support services program, Alnylam Assist®, will offer an in-house team of Case Managers to assist patients with verification of insurance benefits and financial assistance for those who qualify. Patients will also be eligible to receive support from Patient Education Liaisons, who can answer questions about disease and treatment. Physicians and patients can learn more about Alnylam’s comprehensive patient services by visiting AlnylamAssist.com or call 1-833-256-2478.

Visit GIVLAARI.com for more information, including full Prescribing Information.

GIVLAARI Important Safety Information

Contraindications GIVLAARI is contraindicated in patients with known severe hypersensitivity to givosiran. Reactions have included anaphylaxis.

Anaphylactic Reaction Anaphylaxis has occurred with GIVLAARI treatment (