Alnylam Pharmaceuticals Reports Fourth Quarter and Full Year 2020 Financial Results and Highlights Recent Period Activity Achieved Fourth Quarter and Full Year 2020 Global Net Product Revenues of $113 Million and $362 Mi

Achieved Fourth Quarter and Full Year 2020 Global Net Product Revenues of $113 Million and $362 Million, Respectively -

Achieved Regulatory Approvals of OXLUMO in the EU and U.S. and Leqvio , by Partner Novartis, in the EU -

- Launched "Alnylam P5x25" Strategy for Planned Transition to a Top Five Biotech in Market Capitalization Over the Next Five Years -

- Reported Positive Topline Results from HELIOS-A Phase 3 Study of Vutrisiran in Patients with hATTR Amyloidosis with Polyneuropathy -

- Provides 2021 Combined Net Product Revenue Guidance of $610-660 Million, in addition to Collaboration & Royalty Revenue and Operating Expense Guidance -

CAMBRIDGE, Mass.--(BUSINESS WIRE)--February 11, 2021--Alnylam Pharmaceuticals, Inc. (Nasdaq: ALNY), the leading RNAi therapeutics company, today reported its consolidated financial results for the fourth quarter and full year ended December

31, 2020 and reviewed recent business highlights.

"We're very pleased with the 2020 commercial performance for our marketed products, and expect steady and continued growth in 2021 across our product portfolio, driven by improved disease awareness, new patient finding, and geographic

expansion. In the fourth quarter we celebrated the regulatory approvals of our third and fourth commercial medicines: OXLUMO, in the EU and U.S.; and Leqvio, in the EU. We also reported positive topline results from the HELIOS-A Phase 3 study

of vutrisiran, our fifth investigational medicine to achieve that important milestone," said John Maraganore, Ph.D., Chief Executive Officer of Alnylam. "Having exceeded our "Alnylam 2020" vision and goals, we now look to the next

chapter of our Company's story, and are excited to have recently launched our new five-year vision, Alnylam P5x25.' With Alnylam P5x25, we aim to bring transformative medicines in both rare and common

diseases to patients around the world, while advancing a robust and high-yielding pipeline of first and/or best-in-class product candidates from our organic research engine, and delivering exceptional financial performance."

Fourth Quarter 2020 and Recent Significant Corporate Highlights

Commercial Performance

Achieved global net product revenues for the fourth quarter and full year 2020 of $90 million and $306 million, respectively, representing 9.5% quarterly growth compared to Q3 - including 10.4% growth in the U.S. market segment driven by

new patient demand - and over 80% annual growth from full year 2019.

Attained approximately 1,350 patients worldwide on commercial ONPATTRO treatment as of December 31, 2020.

Continued global expansion with achievement of regulatory approval in Taiwan and market access now achieved in over 20 countries.

Achieved global net product revenues for the fourth quarter and full year 2020 of $22 million and $55 million, respectively, representing over 30% quarterly growth compared to Q3.

Attained approximately 200 patients worldwide on commercial GIVLAARI treatment as of December 31, 2020.

Continued strong progress toward establishing value-based agreements (VBAs), with over 10 VBAs finalized to date - including the first state-level VBA with MassHealth - and confirmed access for 94% of covered U.S. lives.

Continued progress with market access efforts across the CEMEA region, with an ongoing launch in Germany, Temporary Authorization for Use (ATU) supply in France, and named patient sales in other countries.

The Company announces today that it has achieved market access in Italy.

For the period following EMA and FDA approval of OXLUMO in late November 2020, observed strong initial U.S. demand with 8 Start Forms received through December 31, 2020.

Achieved global net product revenues for the fourth quarter of approximately $0.3 million representing initial patient demand in Europe.

The Company has actively engaged with U.S. and EU payers toward establishing VBAs, including both Patient Need Adjustment and Prevalence-Based Adjustment features.

The Company announces today that it has completed its first OXLUMO VBA with a major commercial payer, with several more under negotiation.

Achieved significant progress with market access efforts across the CEMEA region, with an ongoing launch in Germany, and ATU supply in France.

Patisiran (the non-proprietary name for ONPATTRO), in development for the treatment of the cardiomyopathy of both hereditary and wild-type ATTR amyloidosis

Continued enrollment in the APOLLO-B Phase 3 study in ATTR amyloidosis patients with cardiomyopathy, with plans to complete enrollment in early 2021.

Vutrisiran, a subcutaneously administered investigational RNAi therapeutic in development for the treatment of ATTR amyloidosis

Reported positive topline results from the HELIOS-A Phase 3 study in hATTR amyloidosis patients with polyneuropathy, with plans to file a New Drug Application (NDA) with the FDA in early 2021.

Continued enrollment in the HELIOS-B Phase 3 study in ATTR amyloidosis patients with cardiomyopathy.

Lumasiran (the non-proprietary name for OXLUMO), for the treatment of primary hyperoxaluria type 1 (PH1)

Presented positive complete results from ILLUMINATE-B, a global Phase 3 pediatric study of lumasiran in PH1 patients less than six years of age, including infants, with preserved renal function.

Completed enrollment in the ILLUMINATE-C Phase 3 study of lumasiran for the treatment of advanced PH1 in patients of all ages.

Leqvio (inclisiran), for the treatment of hypercholesterolemia

Alnylam's partner Novartis received marketing authorization for Leqvio from the European Commission in December 2020.

Novartis received a Complete Response Letter from the FDA in December 2020, due to unresolved facility inspection-related conditions at a third-party manufacturing facility in Europe. Novartis is working closely with the third-party

manufacturer and the FDA to obtain approval as soon as possible, and has guided for a resubmission of its NDA in Q2-Q3 2021.

Fitusiran, in development for the treatment of hemophilia A or B with and without inhibitors

Alnylam's partner, Sanofi, resumed dosing and enrollment in the ATLAS Phase 3 program.

Sanofi announced that fitusiran was granted Fast Track designation by the FDA for all indications.

Early- and mid-stage RNAi therapeutic pipeline programs

Presented positive interim results from the Phase 1 study of ALN-AGT, in development for the treatment of hypertension.

Initiated dosing in the Phase 1 study of ALN-HSD, in development for the treatment of non-alcoholic steatohepatitis (NASH).

Continued enrollment and dosing in the Phase 2 study of cemdisiran monotherapy in IgA nephropathy, and initiated dosing in a Phase 1 study of combination therapy with pozelimab, an anti-C5 monoclonal antibody, in

collaboration with Regeneron.

Alnylam's partner Vir Biotechnology continues enrollment and dosing in a Phase 2 combination trial of ALN-HBV02 (VIR-2218) with pegylated interferon-alpha (PEG-IFN- ).

Continued progress with investigational RNAi therapeutics for CNS and ocular diseases, including advancement of ALN-APP, in development for the treatment of cerebral amyloid angiopathy (CAA) and autosomal dominant Alzheimer's

Disease (ADAD), with an expected CTA filing in mid-2021.

Additional Business Updates

Launched Alnylam P5x25 strategy.

Received recognition from Science Magazine as a Top Biopharma Employer.

Issued the second annual Patient Access Philosophy Report.

Announced new senior leadership appointments:

Tolga Tanguler, Executive Vice President, Chief Commercial Officer

Kasha Witkos, Senior Vice President, Head of CEMEA

Salil Patel, Ph.D., Senior Vice President, Head of Medical Affairs

Agnieszka Gallagher, Senior Vice President, Chief Ethics and Compliance Officer

Alnylam announces today that it intends to present complete 9-month results from the HELIOS-A Phase 3 study of vutrisiran at the American Academy of Neurology (AAN) 2021 Virtual Meeting being held April 17-22, 2021.

In addition, in early 2021, Alnylam intends to:

File an NDA for vutrisiran.

Complete enrollment in the APOLLO-B Phase 3 study of patisiran in patients with ATTR amyloidosis with cardiomyopathy.

Initiate study of biannual dosing regimen with vutrisiran.

Achieve regulatory approval for OXLUMO in Brazil.

Financial Results for the Quarter and Year Ended December 31, 2020

"We saw very strong performance from our commercial products in 2020, even with headwinds from the COVID-19 pandemic. ONPATTRO demonstrated more than 80% growth from 2019 and GIVLAARI achieved $55 million in full year revenues, an excellent

start for this important medicine in its launch year. In 2021, we expect continued growth from both products, and look forward to now leveraging our global commercial capabilities for the launch of OXLUMO, which was recently approved in the

U.S. and EU," said Jeff Poulton, Chief Financial Officer of Alnylam. "Today, we are guiding that we expect to achieve between $610 million and $660 million in combined net product revenues for full-year 2021 across our three wholly owned

commercial brands, representing over 75% growth at the midpoint of the range as compared with our 2020 results. In addition, we intend to continue to demonstrate disciplined investment in our operations as we transition toward a

self-sustainable financial profile."

Financial Highlights

(in thousands, except per share amounts)

Net Product Revenues

Combined net product revenues were $112.8 million in the fourth quarter 2020 representing 102% growth from the fourth quarter 2019. The strong growth primarily resulted from an increase in patients on therapy driven by growth in

established markets and continued global expansion of ONPATTRO and GIVLAARI, as well as initial net product revenues from OXLUMO following regulatory approval in the fourth quarter of 2020.

Combined net product revenues were $361.5 million in the full-year 2020 representing 117% growth from the full-year 2019. The strong growth was driven by the continued global expansion of ONPATTRO and the global launch of GIVLAARI.

Net Revenues from Collaborations

Net revenues from collaborations were $50.7 million in the fourth quarter 2020, an increase from $15.7 million in the fourth quarter 2019, primarily due to the achievement of a $15.0 million milestone related to Leqvio approval in Europe

under the Novartis collaboration agreement, as well as an increase in revenue recognized in connection with our collaboration agreement with Regeneron.

Net revenues from collaborations were $131.3 million for the full-year 2020, an increase from $53.2 million in 2019, primarily due to increases in revenue recognized from our collaborations with Regeneron, Vir, and Novartis.

Research & Development (R&D) and Selling, General & Administrative (SG&A) Expenses

R&D expenses decreased on a GAAP basis in the fourth quarter 2020 compared to the same period in 2019, primarily due to a decrease in manufacturing activity for clinical drug and a decrease in stock-based compensation as a result of

the achievement of certain performance-based milestones in 2019. R&D expenses decreased on a non-GAAP basis in the fourth quarter 2020 compared to the same period in 2019 primarily due to decreases in manufacturing activity for clinical

For the full-year 2020, R&D expenses were relatively consistent on a GAAP basis and increased on a non-GAAP basis, compared to the same period in 2019, primarily due to increased expenses associated with clinical and preclinical

activities, personnel, and facilities as we continue to support our long-term strategic growth offset by decreased license fees associated with regulatory filings.

SG&A expenses increased in the fourth quarter 2020 compared to the same period in 2019 on a GAAP and non-GAAP basis primarily due to increased investment in commercial and medical affairs activity to support the ongoing launches of

ONPATTRO and GIVLAARI and launch activities for OXLUMO.

For the full-year 2020, SG&A expenses increased on a GAAP and non-GAAP basis, compared to the same period in 2019, primarily due to increased investment in commercial and medical affairs activity to support the ongoing launches of

ONPATTRO and GIVLAARI and initial launch of OXLUMO. SG&A expenses on a GAAP basis also increased for the full-year 2020, compared to the same period in 2019, due to a change in estimate of contingent liabilities related to our arbitration

Cash and Investments

Cash, cash equivalents, and marketable debt and equity securities were $1.87 billion at the end of the fourth quarter 2020 compared to $1.54 billion at the end of 2019. The increase was primarily due to $800.0 million in proceeds from the

sale of future royalties, the issuance of common stock and the initial draw down under our credit agreement in each case associated with our strategic financing collaboration with The Blackstone Group Inc. and certain of its affiliates,

partially offset by cash used in our operations to advance our pipeline and support overall growth.

A reconciliation of GAAP to non-GAAP results for the current quarter is included in the tables of this press release.

2021 Financial Guidance

Full year 2021 financial guidance consists of the following: