Dicerna Pharmaceuticals : Corporate Overview

Corporate Overview

Discovery to Commercialization RNAi Platform

July 2021

Forward-Looking Statements

This presentation has been prepared by Dicerna Pharmaceuticals, Inc. ("we," "us," "our," "Dicerna," or the "Company") and includes forward-looking statements. Forward-looking statements are subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied in such statements. Examples of forward-looking statements include, among others, statements we make regarding: (i) the therapeutic and commercial potential of nedosiran, RG6346, belcesiran (formerly DCR-A1AT),DCR-AUD and the GalXC™ platform; (ii) expectations about our cash, cash equivalents and marketable securities; (iii) research and development plans and timelines, as well as regulatory pathways and plans, related to nedosiran, RG6346, belcesiran, DCR-AUD, GalXC and GalXC-Plus™; (iv) the potential of Dicerna's technology and drug candidates in the Company's research and development pipeline, including our pipeline expansion efforts and expectations;

1. the Company's collaborations with Novo Nordisk A/S; Roche; Eli Lilly and Company; Alexion Pharmaceuticals, Inc.; Boehringer Ingelheim International GmbH; and Alnylam Pharmaceuticals, Inc.; and (vi) the Company's strategy, business plans and focus. The process by which an early-stage investigational therapy such as nedosiran and an early-stage platform such as GalXC could potentially lead to an approved product is long and subject to significant risks. Applicable risks and uncertainties include, but are not limited to, those risks identified under the heading "Risk Factors" included in the Company's most recent Form 10-K filing and in other subsequent filings with the Securities and Exchange Commission. These risks and uncertainties include, among others, the impact to, and potential for delays in, the current and future conduct of the business of the Company, its clinical programs and operations as a result of the COVID-19 pandemic; the cost, timing and results of preclinical studies and clinical trials and other development activities; the likelihood of Dicerna's clinical programs being executed within timelines provided and reliance on the Company's contract research organizations and predictability of timely enrollment of subjects and patients to advance Dicerna's clinical trials; the potential for future data to alter initial, interim and preliminary results of clinical trials, including the multidose data from the PHYOX™3 trial of nedosiran; the unpredictability of the duration and results of the regulatory review of Investigational New Drug (IND) applications and Clinical Trial Applications that are necessary to continue to advance and progress the Company's clinical programs and the regulatory review of submissions relevant to regulatory agencies for marketing approvals, including New Drug Applications (NDAs); market acceptance for approved products and innovative therapeutic treatments; competition; the possible impairment of, inability to obtain and costs of obtaining needed intellectual property rights; possible safety or efficacy concerns that could emerge as new data are generated in R&D; that the Company may not realize the intended benefits of its collaborations; general business, financial and accounting risks; and the risks and potential outcomes from litigation.

Dicerna is providing this information as of this date and does not undertake any obligation to update or revise it, whether as a result of new information, future events or circumstances or otherwise. Additional information concerning Dicerna and its business may be available in press releases or other public announcements and public filings made after the date of this information.

Dicerna™, GalXC™, GalXC-Plus™ and PHYOX™ are trademarks of Dicerna Pharmaceuticals, Inc.

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The RNAi Modality Has Come of Age

RNAi Has Been Successful Where Traditional Modalities Have Not

Gene Targeting Across Multiple Tissue Types

Approved Products in Multiple Disease Areas

Simple & Convenient Dosing Regimens

Multiple Committed Large Pharmas

founded to specialize in RNAi

Partner of Choice: Several large pharmas have chosen Dicerna for RNAi collaboration

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RNAi Delivery Is Extending to Multiple Tissues Beyond the Liver

The Future Is Bright

Liver

Central Nervous System

Muscle

Adipose

Tumor-Associated Immune Cells Additional Tissues

Rare disease, HBV, cholesterol, NASH, cardiometabolic diseases, AUD and more

Alzheimer's, Parkinson's, frontotemporal dementia, Huntington's, spinal cord injury, other rare diseases and more

Myotonic dystrophy, other rare diseases

Diabetes, obesity, rare diseases and more

Immuno-oncology

Diseases of the lung, eye, kidney, etc.

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Dicerna Is an Engine of Discovery and Development

Proprietary and Collaboration Program Portfolios Provide for Consistent Funding Stream

Core Clinical Pipeline

Current pipeline yields multiple major milestones over next year+

• Nedosiran: A differentiated potential therapy for all primary hyperoxaluria (PH) types (PH1, PH2 and PH3)
• RG6346: Potential best-in-class therapeutic with strong and durable HBsAg reduction for treatment of chronic hepatitis B virus (HBV) infection
• Belcesiran: Targeting alpha-1 antitrypsin deficiency-associated liver disease (AATLD)
• DCR-AUD: Targeting ALDH2 for alcohol use disorder (AUD)

Shots on Goal

• 20+ discovery programs in multiple tissue types
• 8 programs in IND-enabling studies
• 1st partner compound already in clinic

De-Risked Technology Platform

• Supported by multiple clinical programs
• Validated by multiple major pharma collaborations
• Delivery to multiple tissues: liver, nervous system, muscle, adipose, tumor-associated immune cells and more

Milestone-Rich 2021

Key data readouts, NDA filing, clinical entries and collaboration payments

• $544.9M in cash, cash equivalents and marketable securities at 3/31/2021
• $180 million cash payment received in April 2021 as upfront for sale of royalty interest
• Expect little change between 2020 and 2021 year-end cash positions, assuming no follow-on stock offering

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