Phathom Pharmaceuticals : First Quarter 2024 Earnings Call – May 2024

FIRST QUARTER 2024 EARNINGS CONFERENCE CALL

MAY 2024

NASDAQ: PHAT

Today's Agenda

Business Update

Terrie Curran, President & Chief Executive Officer

US Commercial Launch Progress

Martin Gilligan, Chief Commercial Officer

First Quarter 2024 Results

Molly Henderson, Chief Financial & Business Officer

Closing Remarks

Terrie Curran, President & Chief Executive Officer

Question & Answer

Terrie Curran, President & Chief Executive Officer Martin Gilligan, Chief Commercial Officer

Molly Henderson, Chief Financial & Business Officer Azmi Nabulsi, Chief Operating Officer

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Safe harbor

This presentation contains forward-looking statements. All statements other than statements of historical facts contained in this presentation, including statements regarding our future results of operations and financial position, anticipated milestones, anticipated cash runway, expectations of generating stability data necessary to support the proposed shelf life of vonoprazan, business strategy, prospective products, product approvals, research and development costs, timing and likelihood of success, plans and objectives of management for future operations, and future results of current and anticipated products, are forward-looking statements.

In some cases, you can identify forward-looking statements by terms such as "may," "will," "should," "expect," "plan," "anticipate," "could," "intend," "target," "project," "contemplates," "believes," "estimates," "predicts," "potential" or "continue" or the negative of these terms or other similar expressions. These statements involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. These risks, uncertainties and other factors include, without limitation: our ability successfully to commercialize approved products containing vonoprazan; our new drug application for non-erosive GERD may not be approved by the FDA; our planned clinical trials of vonoprazan as an as need treatment for non-erosive GERD or for eosinophilic esophagitis may not successfully be initiated or completed; we may not be successful in expanding commercial coverage for our approved products; the inherent risks of clinical development of vonoprazan; our dependence on third parties in connection with product manufacturing, research and preclinical and clinical testing; regulatory developments in the United States and foreign countries; unexpected adverse side effects or inadequate efficacy of vonoprazan that may limit its development, regulatory approval and/or commercialization, or may result in recalls or product liability claims; our ability to obtain and maintain intellectual property protection and non-patent regulatory exclusivity for approved products containing vonoprazan; our ability to comply with our license agreement with Takeda; our ability to achieve and maintain adequate levels of coverage and reimbursement for vonoprazan; the availability of additional funds under our revenue interest financing agreement and term loan agreement; the sufficiency of our capital to fund our operations; and other risks described in our filings with the Securities and Exchange Commission (SEC), including our most recent Annual Report on Form 10-K and any subsequent filings with the SEC. You are cautioned to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and we undertake no obligation to revise or update this presentation to reflect events or circumstances after the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement, which is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995.

This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions, and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk.

This presentation contains non-GAAP financial measures, which should be considered only a supplement to, and not a substitute for or superior to, GAAP measures. Refer to the Reconciliation of Non-GAAP Financial Measures to GAAP Results table on pages 17 and 18 of this presentation.

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Business Update

Terrie Curran, President & Chief Executive Officer

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Focused on three core goals during the early stages of launch

Communicate clinical superiority vs. a PPI

Drive brand awareness and demand

Build access for	®
patients

5

I had coffee today for

Great progress made executing on VOQUEZNA launch goals

Clinical Superiority

Brand Awareness

Patient Access

Express Scripts National Formularies

Cigna Healthcare

Formularies

This medication and my [GI] saved my life. I suffered for months and had given up. Could not eat or lie down. Was in constant

pain. But now I am on the way to healing.

first time in months.1

	1	Actual VOQUEZNA patient. Results not typical.
	2	Unique prescriptions written; IQVIA + BlinkRx as of 4/26/24.
6	3	IQVIA + BlinkRx as of 4/26/24.
4	Per MMIT formulary lookup tool as of 5/8/2024.

43K+

prescriptions written2 17.5K+

prescriptions filled3

• 72M

commercial

lives covered4

Approaching potential Non-Erosive GERD launch and planned development

Prepared for an immediate launch into Non-Erosive GERD Daily Dosing

July 19, 2024	~15M	Similar Patient	Same Target
Action Date	Dx & Tx Adults1	Journey	Writers

Planned

Development

in 2024

As Needed treatment of heartburn	Treatment of Eosinophilic Esophagitis
associated with Non-ErosiveGERD	(EoE) for adult & pediatric use
»	Positive Phase 2 results	» Planning to initiate
»	Planning to initiate	Phase 2 trial in 2024

Phase 3 trial in 2024

7	1 Diagnosed and treated annually with a prescription.

RAPID

POTENT

DURABLE

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US Commercial Launch Progress

Martin Gilligan, Chief Commercial Officer

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The commercial launch of VOQUEZNA continues to build momentum

43,000+	17,500+	3,800+
Total	Filled	Unique
VOQUEZNA	VOQUEZNA	VOQUEZNA
Demand1	Prescriptions2	Writers3
Previously: 14,000+ (as of 3/3/24)	Previously: 3,800+ (as of 2/23/24)	Previously: 1,200+ (as of 2/16/24)

	1	Unique prescriptions written; IQVIA + BlinkRx as of 4/26/24.
10	2	IQVIA + BlinkRx as of 4/26/24.
3	IQVIA + BlinkRx as of 4/19/24.