Dicerna Pharmaceuticals : Corporate Overview

Corporate Overview

Creating New Medicines From GalXC™ RNAi Technology Platform

September 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 as well as those of RG6346, belcesiran (formerly DCR-A1AT),DCR-AUD and our GalXC™ and GalXC Plus™ RNAi technology; (ii) our research and development plans and timelines for nedosiran as well as those for RG6346, belcesiran, DCR-AUD, GalXC and GalXC-Plus; (iii) our regulatory pathways, plans and timelines for nedosiran as well as those for RG6346, belcesiran, DCR-AUD, GalXC and GalXC-Plus; (iv) the Company's strategy, business plans and focus; (v) the Company's expectations about our cash, cash equivalents and held-to-maturity investments; (vi) the potential of Dicerna's technology and drug candidates, including our pipeline expansion efforts and expectations; and (vii) 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. 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 subsequent filings with the Securities and Exchange Commission. These risks and uncertainties include, among others, the potential for additional or future data to alter initial, interim and preliminary results of clinical trials; positive data from preclinical studies and earlier clinical trials may not be predictive of results from subsequent preclinical studies and clinical trials; the results of clinical trials may produce negative, inconclusive or uncompetitive results; possible safety, efficacy concerns could emerge as new data are generated in R&D and/or clinical trials; 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; our reliance on the Company's contract research and manufacturing organizations; the unpredictability of timely enrollment of subjects and patients to advance Dicerna's clinical trials; the unpredictability of the duration and results of the regulatory review of Investigational New Drug (IND) applications and Clinical Trial Applications (CTAs) 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; 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

Dicerna was 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 primary hyperoxaluria (PH)
• 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
• 7 programs in IND-enabling studies
• 2nd 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

• $709.6M in cash, cash equivalents and held-to- maturity investments at 6/30/2021
• $180 million cash payment received in April 2021 as upfront for sale of royalty interest
• Expected cash runway into 2025

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