Alnylam Pharmaceuticals Reports First Quarter 2018 Financial Results and Highlights Recent Period Activity - Presented Positive New Clinical Results from APOLLO Phase 3 Study of Patisiran, and Phase 1 and Phase 1/2 Open-

Pharmaceuticals Reports First Quarter 2018 Financial Results and

Highlights Recent Period Activity

Presented Positive New Clinical Results from APOLLO Phase 3 Study of

Patisiran, and Phase 1 and Phase 1/2 Open-Label Extension (OLE) Studies

Advanced Two Additional RNAi Therapeutics in Phase 3 Development:

Inclisiran in ORION-9, -10, and -11 Studies, and Fitusiran in the ATLAS

Company Provides Positive New Development Updates on Phase 3 Programs

for Givosiran and Lumasiran -

Maintained Strong Balance Sheet with $1.6 Billion in Cash and Plans to

End 2018 with Approximately $1.0 Billion in Cash -

CAMBRIDGE, Mass.--(BUSINESS WIRE)--May 3, 2018--Alnylam Pharmaceuticals,

Inc. (Nasdaq: ALNY), the leading RNAi therapeutics company, today

reported its consolidated financial results for the first quarter 2018

and highlighted recent progress in advancing its pipeline.

"We had a very productive first quarter of 2018 and recent period. We're

working in close coordination with global regulatory authorities on

bringing investigational patisiran to patients around the world. In

parallel, we are actively preparing for our U.S. launch of patisiran,

following an anticipated mid-2018 FDA approval. With our U.S. field team

on-boarded, we believe we are launch ready' and prepared to get

patisiran to patients as soon as it is approved," said John Maraganore,

Ph.D., Chief Executive Officer of Alnylam. "Beyond patisiran, we were

very pleased to announce that we've completed enrollment of the first 30

patients in our ENVISION Phase 3 study with givosiran, putting us on

track to complete an interim analysis in the September timeframe. We are

also excited to announce that we've reached alignment with the U.S. FDA

on a pivotal study design on our lumasiran program, significantly

accelerating our development efforts for this investigational RNAi

therapeutic. In sum, we believe our efforts position the Company to

achieve its Alnylam 2020 goals of building a multi-product,

commercial-stage company with a deep clinical-stage pipeline and robust

product engine by the end of 2020, a profile rarely achieved in the

First Quarter 2018 and Recent Significant Corporate Highlights

Advanced patisiran, an investigational RNAi therapeutic for the

treatment of patients with hereditary ATTR amyloidosis.

Presented new data from the APOLLO Phase 3 study, including:

Data at the International Symposium on Amyloidosis (ISA),

including results on the effects of patisiran on

cardiomyopathy manifestations; and,

New data from a post-hoc analysis presented at the American

Academy of Neurology (AAN) meeting on the effects of patisiran

on the composite rate of all-cause hospitalization and

Received acceptance from the United States Food and Drug

Administration (FDA) and the European Medicines Agency (EMA) of

patisiran's New Drug Application (NDA) and Marketing Authorisation

Application (MAA), respectively.

The Company is continuing to fulfill requests from treating

physicians for early access or compassionate use of patisiran, and

to date, more than 150 eligible patients have begun treatment with

patisiran under these programs in the U.S. and EU.

Advanced ALN-TTRsc02, a subcutaneously administered investigational

RNAi therapeutic in development for the treatment of ATTR amyloidosis,

with updated data from the Phase 1 study presented at ISA, and receipt

of a positive opinion from the EMA Committee for Orphan Medicinal

Products (COMP) for Orphan Drug Designation in the European Union for

ALN-TTRsc02 for the treatment of ATTR amyloidosis.

Advanced givosiran, an investigational RNAi therapeutic in development

for the treatment of acute hepatic porphyrias (AHPs).

Presented new positive Phase 1 and Phase 1/2 open-label extension

(OLE) study results at the European Association for the Study of

the Liver (EASL) meeting.

The Company announces today that it has completed enrollment of

the first 30 patients in the ENVISION Phase 3 study, which

comprise the interim analysis cohort for a potential accelerated

approval by the FDA. This positions the Company to report interim

analysis results in the September timeframe and, pending FDA

review of the program at the time of interim analysis and assuming

positive results, the Company expects to submit an NDA at or

around year-end 2018.

The Company also announces today that notwithstanding productive

conversations with the EMA on a potential accelerated approval

pathway for givosiran, the Company has decided to file an MAA on

the full dataset from ENVISION, expected in 2019, to optimize

market access in Europe.

Expanded the Alnylam Act program to include no-charge,

third-party genetic testing and counseling requested by enrolled

physicians for individuals who may carry a gene mutation known to

be associated with AHPs. The Company announces that out of

approximately 50 samples submitted to date by physicians with

patients with symptoms consistent with AHPs, eight have tested

positive for known mutations associated with AHPs.

Advanced lumasiran, an investigational RNAi therapeutic in development

for the treatment of primary hyperoxaluria type 1 (PH1).

Retained global rights to the program following the decision by

Sanofi Genzyme to decline its opt-in for lumasiran's development

and commercialization.

As announced earlier today, the Company has reached alignment with

the FDA on a pivotal study design for lumasiran with reduction at

six months in urinary oxalate as the primary endpoint. In

addition, the pivotal study will comprise approximately 25

patients with PH1. Alnylam is now guiding that it expects to

initiate the lumasiran Phase 3 trial in mid-2018 with results

expected in 2019. If positive, Alnylam expects to file an NDA in

Lumasiran was recently granted Breakthrough Therapy Designation by

the FDA as well as access to the EMA's Priority Medicines (PRIME)

With partner Sanofi, advanced fitusiran - an investigational RNAi

therapeutic in development for the treatment of hemophilia A and B

with or without inhibitors - with the initiation of dosing in the

ATLAS Phase 3 program. The Company expects to fully transition

development and commercialization leadership of the fitusiran program