Praxis Precision Medicines : August 2022 Corporate Presentation

CORPORATE OVERVIEW

August 2022

Forward-looking statements

This presentation may contain "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 relating to our business, operations, and financial conditions, including but not limited to express or implied statements regarding the current beliefs, expectations and assumptions regarding the future of our business, future plans and strategies, our development plans, our preclinical and clinical results and other future conditions. Any forward-looking statements in this presentation are based on management's current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this presentation, including, without limitation, risks relating to: (i) the success and timing of our ongoing clinical trials, (ii) the success and timing of our product development activities and initiating clinical trials, (iii) the success and timing of our collaboration partners' product development activities, (iv) our ability to obtain and maintain regulatory approval of any of our product candidates,

(v) our plans to research, discover and develop additional product candidates, (vi) our ability to enter into collaborations for the development of new product candidates, (vii) our ability to establish manufacturing capabilities, and our and our collaboration partners' abilities to manufacture our product candidates and scale production, (viii) our ability to meet any specific milestones set forth herein, and (ix) uncertainties and assumptions regarding the impact of the COVID-19 pandemic on our business, operations, clinical trials, supply chain, strategy, goals and anticipated timelines. New risks and uncertainties may emerge from time to time, and it is not possible to predict all risks and uncertainties. Except as required by applicable law, we do not plan to publicly update or revise any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise. Although we believe the expectations reflected in such forward-looking statements are reasonable, we can give no assurance that such expectations will prove to be correct. Accordingly, readers are cautioned not to place undue reliance on these forward-looking statements.

For further information regarding the risks, uncertainties and other factors that may cause differences between our expectations and actual results, you should review the "Risk Factors" section of our Annual Report on Form 10-K filed for the year ended December 31, 2021, our Quarterly Reports on Form 10-Q and other filings with the Securities and Exchange Commission.

Certain information contained in this presentation relates to or is based on studies, publications, surveys and other data obtained from third-party sources and our own internal estimates and research. While we believe these third-party sources to be reliable as of the date of this presentation, we have not independently verified, and make no representation as to the adequacy, fairness, accuracy or completeness of, any information obtained from third-party sources. In addition, all of the market data included in this presentation involves a number of assumptions and limitations, and there can be no guarantee as to the accuracy or reliability of such assumptions. Finally, while we believe our own internal research is reliable, such research has not been verified by any independent source.

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Developing New Classes of Treatments

INSPIRED BY THE GENETICS OF EPILEPSY

DRD3

HTT

FMR1

OPA1

	CACNA1G
CACNA1A	GABRB3	CDKL5
KCNA1	KCN1A	DNM1
SLC1A3	SCN8A	UNC79
SETX	SCN2A	TRIM3
RFC1		PCDH19
		CACNA1A
			TPH2
MOVEMENT	EPILEPSY	PSYCHIATRY	FKBP2
HTR2A
	GABRB3	SYNGAP1
	KCNT1
	SHANK3
	SCN1A

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Targeting common & rare diseases connected by neuronal imbalance

				REGISTRATION
FOCUS AREA	PRECLINICAL	IND / PHASE ONE	PHASE TWO	ENABLING

MOVEMENT DISORDERS

EPILEPSY

PSYCHIATRY

PRAX-050

Undisclosed

PRAX-090 (ASO)	PRAX-020
SYNGAP1	KCNT1
PRAX-100 (ASO)	PRAX-628
SCN2A LoF	Focal Epilepsy
PRAX-030	PRAX-080 (ASO)
Undisclosed	PCDH19

PRAX-944

Essential Tremor

PRAX-944

Parkinson's Disease

PRAX-222 (ASO)

SCN2A GoF DEE

PRAX-562

DEEs

PRAX-114

MDD

*PRAX-222 is in collaboration with Ionis Pharmaceuticals and RogCon, Inc. SCN2A-LOF, SYNGAP1 & PCDH19 ASOs are a collaboration with The Florey Institute of Neuroscience and Mental Health.

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Praxis is built on four key pillars

TARGETS IDENTIFIED THROUGH

GENETICS

DEVELOPMENT INFORMED BY	CLINICAL DEVELOPMENT PATHS TO POC ARE
TRANSLATIONAL	RIGOROUS &
TOOLS	EFFICIENT

DEVELOPMENT STRATEGIES ARE

PATIENT-GUIDED

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