PTC Therapeutics : Corporate Presentation – May 2024

PTC Therapeutics

May 2024

Patient Living with PKU

Forward-Looking Statements

This presentation contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. All statements contained in this presentation, other than statements of historic fact, are forward-looking statements, including statements regarding: the future expectations, plans and prospects for PTC, including with respect to the expected timing of clinical trials and studies, availability of data, regulatory submissions and responses, commercialization and other matters with respect to its products and product candidates; PTC's strategy, future operations, future financial position, future revenues, projected costs; the extent, timing and financial aspects of our strategic pipeline prioritization and reductions in workforce; and the objectives of management. Other forward-looking statements may be identified by the words, "guidance", "plan," "anticipate," "believe," "estimate," "expect," "intend," "may," "target," "potential," "will," "would," "could," "should," "continue," and similar expressions.

PTC's actual results, performance or achievements could differ materially from those expressed or implied by forward-looking statements it makes as a result of a variety of risks and uncertainties, including those related to: the outcome of pricing, coverage and reimbursement negotiations with third party payors for PTC's products or product candidates that PTC commercializes or may commercialize in the future; PTC's ability to maintain its marketing authorization of Translarna for the treatment of nmDMD in Brazil, Russia, the European Economic Area (EEA) and other regions, including whether the European Commission adopts the negative opinion from the Committee for Medicinal Products for Human Use (CHMP) for the conditional marketing authorization for Translarna in the EEA; PTC's ability to use the results of Study 041, a randomized, 18-month,placebo-controlled clinical trial of Translarna for the treatment of nmDMD followed by an 18-monthopen-label extension, and from its international drug registry study to support a marketing approval for Translarna for the treatment of nmDMD in the United States; whether investigators agree with PTC's interpretation of the results of clinical trials and the totality of clinical data from our trials in Translarna; expectations with respect to Upstaza, including any regulatory submissions and potential approvals, commercialization, manufacturing capabilities, the potential achievement of development, regulatory and sales milestones and contingent payments that PTC may be obligated to make; expectations with respect to the commercialization of Evrysdi under our SMA collaboration; expectations with respect to the commercialization of Tegsedi and Waylivra; the timing of and actual expenses incurred in connection with the discontinuation of PTC's preclinical and early research programs in gene therapy and reductions in workforce, which may be in different periods and may be materially higher than estimated; the savings that may result from the discontinuation of PTC's strategic pipeline prioritization and reductions in workforce, which may be materially less than expected; significant business effects, including the effects of industry, market, economic, political or regulatory conditions; changes in tax and other laws, regulations, rates and policies; the eligible patient base and commercial potential of PTC's products and product candidates; PTC's scientific approach and general development progress; the potential financial impact and benefits of PTC's leased biologics manufacturing facility; PTC's ability to satisfy its obligations under the terms of its lease agreements, including for its leased biologics manufacturing facility; the sufficiency of PTC's cash resources and its ability to obtain adequate financing in the future for its foreseeable and unforeseeable operating expenses and capital expenditures; and the factors discussed in the "Risk Factors" section of PTC's most recent Quarterly Report on Form 10-Q and Annual Report on Form 10-K, as well as any updates to these risk factors filed from time to time in PTC's other filings with the SEC. You are urged to carefully consider all such factors.

As with any pharmaceutical under development, there are significant risks in the development, regulatory approval and commercialization of new products. There are no guarantees that any product will receive or maintain regulatory approval in any territory, or prove to be commercially successful, including Translarna, Emflaza, Upstaza, Evrysdi, Tegsedi or Waylivra.

The forward-looking statements contained herein represent PTC's views only as of the date of this presentation and PTC does not undertake or plan to update or revise any such forward-looking statements to reflect actual results or changes in plans, prospects, assumptions, estimates or projections, or other circumstances occurring after the date of this presentation except as required by law.

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Corporate Presentation - May 2024

Building the PTC of the Future

Focus	OPEX
Reduction

Right Sizing	Royalty
	Financing

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Corporate Presentation - May 2024

PTC Strategy Leverages Innovative Science, Passionate Team and Strong Cash Position

Splicing	Ferroptosis and
Innovative Science	Inflammation

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Corporate Presentation - May 2024

PTC Strategy Leverages Innovative Science, Passionate Team and Strong Cash Position

Innovative Science	Therapeutic	Neurology	Metabolism
Expertise

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Corporate Presentation - May 2024

PTC Strategy Leverages Innovative Science, Passionate Team and Strong Cash Position

Europe

Innovative Science	Therapeutic	Global Commercial
Expertise*	Infrastructure

United States

Asia Pacific

Latin America

Middle East &

North Africa

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Corporate Presentation - May 2024

Robust Portfolio to Support Growth & Value Creation

Development

Sepiapterin (PKU)	Phase 1	Phase 2	Phase 2/3	Phase 3	NDA Stage
Vatiquinone (FA)	Phase 1	Phase 2	Phase 2/3	Phase 3	NDA Stage
Utreloxastat (ALS)	Phase 1	Phase 2	Phase 2
PTC518 (HD)	Phase 1	Phase 2
Undisclosed (Myopathies)	Phase 1

Research	Splicing Platform	Ferroptosis and Inflammation Platform
	SCA-3	Undisclosed
	MAP-tau	(Neurodegenerative Diseases)
	Undisclosed
	Undisclosed
	(Pediatric Neurodevelopment Disorders)
	(Movement Disorders)

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Corporate Presentation - May 2024

Key Expected Regulatory & Clinical Milestones in 2024

PTC518

Upstaza	Sepiapterin PKU	Translarna nmDMD	Sepiapterin PKU
BLA Submission	MAA Submission	NDA Resubmission	NDA Submission
		Interim Results

Q1

Q2

Q3

Utreloxastat

t

Topline Results

Q4

Vatiquinone FA

NDA Submission

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Corporate Presentation - May 2024

Sepiapterin

PKU Program

Patient Living with PKU

APHENITY Results Demonstrate Meaningful Benefit of Sepiapterin in PKU Patients

The primary endpoint was reached in the placebo-controlled portion of the study with statistically significant reductions in blood Phe levels (p< 0.0001)

94% of patients ≥ 12 years with blood Phe ≥ 600 µmol/L at baseline achieved a reduction in blood Phe to reach guideline target

A substantial reduction in blood Phe levels from baseline was observed in both the primary analysis population (63%) and the subset of participants with classical PKU (69%)

Sepiapterin was well tolerated with no serious adverse events

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Corporate Presentation - May 2024

Phe, phenylalanine; PKU, phenylketonuria.