Amylyx Pharmaceuticals : Corporate Presentation September 2023

Investor Presentation

September 2023

photo in memory of Mick, a husband and father, who was a gifted tattoo artist and musician

Disclaimer

Statements contained in this presentation regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Such statements include, but are not limited to, statements regarding the potential approval of AMX0035 for the treatment of ALS in countries other than Canada and the United States; statements regarding the timing of any regulatory re-examination process in Europe; the potential of AMX0035 as a treatment for ALS and the Company's plans to explore the use of AMX0035 for other neurodegenerative diseases, including progressive surpranuclear palsy (PSP) and Wolfram syndrome (WS); statements regarding the timing of clinical trials for PSP and/or WS; the potential market acceptance and market opportunity for RELYVRIO®; as well as access to and coverage for RELYVRIO; and expectations regarding our longer-term strategy. Any forward-looking statements in this presentation are based on management's current expectations of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially and adversely from those set forth in or implied by such forward-looking statements. Risks that contribute to the uncertain nature of the forward-looking statements include: the success, cost, and timing of Amylyx' program development activities, including ongoing and planned clinical trials, Amylyx' ability to successfully market RELYVRIO in the United States, Amylyx' ability to execute on its commercial and regulatory strategy, regulatory developments, expectations regarding the timing of EMA review of AMX0035 for the treatment of ALS, Amylyx' ability to fund operations, and the impact that the COVID-19 pandemic will have on Amylyx' operations, as well as the risks and uncertainties set forth in Amylyx' United States Securities and Exchange Commission (SEC) filings, including Amylyx' Annual Report on Form 10-K for the year ended December 31, 2022, and subsequent filings with the SEC. All forward-looking statements contained in this presentation speak only as of the date on which they were made. Amylyx undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made.

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Amylyx Highlights

1st	RELYVRIO® / ALBRIOZA™ / AMX0035

First and only approved drug for adults with ALS to demonstrate a statistically significant benefit in function in a clinical trial as well as a survival benefit in a longer-term post hoc analysis

Strong Global IP Position

Composition of matter patents issued; NCE exclusivity received; orphan drug exclusivity received

Approved in the United States and Canada

June		Sep.	Fall
2022		2022	2023

ALBRIOZA	RELYVRIO	Final CHMP
approved for use	approved	opinion post
with conditions		re-examination*

Research Priorities

Evaluating AMX0035 in new indications, including Wolfram syndrome and progressive supranuclear palsy, and building a neurodegenerative pipeline

* Pending CHMP re-examination process in Europe following negative CHMP Opinion in June 2023.

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Why ALS

We need to work on the ALS clock… I lost the privilege of working on the human clock on January 6, 2018. My clock is a lot faster.

Sandy Morris, 51-year-old mother of three, person who lived with ALS

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ALS is Relentlessly Progressive and Universally Fatal

• Significant unmet need for new treatment options

• ALS leads to deteriorating muscle function, the inability to move and speak, respiratory paralysis, and death1,2

photo in memory of Eric, a husband and father, who was a courageous skydiver and Army veteran

>90%

of people living with ALS have no family history of the disease

~50%

of people with ALS will pass away in about 2 years from diagnosis3

References: 1. Brown RH, Al-ChalabiA. N Engl J Med. 2017;377(2):162-172. 2. Al-ChalabiA, et al. Lancet Neurol. 2016;15(11):1182-1194. 3. Knibb JA, Keren N, Kulka A, et al. J Neurol Neurosurg Psychiatry. 2016;87(12):1361-1367.

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