Amphastar Pharmaceuticals : Wells Fargo Presentation

2021 Wells Fargo Virtual Healthcare Conference

September 9, 2021

Forward Looking Statements

This presentation and the accompanying oral presentation contain forward-looking statements that are based on our management's current expectations and assumptions and on information currently available to management. Forward-looking statements include all statements other than statements of historical fact contained in this presentation, including, but not limited to, information concerning our business plans and objectives, potential growth opportunities, product development, regulatory approvals, market potential, efficiencies, competitive position, and industry environment, among other statements.

All statements in this presentation referenced that are not historical are forward-looking statements, including, among other things, statements relating to our expectations regarding future financial performance, backlog, sales and marketing of our products, market size and growth, product development, the timing of FDA filings or approvals, including the DMFs of ANP, the timing of product launches, acquisitions and other matters related to our pipeline of product candidates, our share buyback program and other future events, such as the impact of the COVID-19 pandemic including its variants and related responses of business and governments to the pandemic on our operations and personnel, and on commercial activity and demand across our business operations and results of operations. These statements are not facts but rather are based on Amphastar's historical performance and our current expectations, estimates, and projections regarding our business, operations, and other similar or related factors. Words such as "may," "might," "will," "could," "would," "should," "anticipate," "predict," "potential," "continue," "expect," "intend," "plan," "project," "believe," "estimate," and other similar or related expressions are used to identify these forward-looking statements, although not all forward-looking statements contain these words. You should not place undue reliance on forward-looking statements because they involve known and unknown risks, uncertainties, and assumptions that are difficult or impossible to predict and, in some cases, beyond Amphastar's control. Actual results may differ materially from those in the forward-looking statements as a result of a number of factors, including those described in Amphastar's filings with the Securities and Exchange Commission, including in our Annual Report on Form 10-K for the year ended December 31, 2020, filed with the SEC on March 15, 2021. In particular, the extent of COVID-19's impact on our business will depend on several factors, including the severity, duration and extent of the pandemic including its variants, as well as actions taken by governments, businesses, and consumers in response to the pandemic, all of which continue to evolve and remain uncertain at this time. You can locate these reports through our website at http://ir.amphastar.com and on the SEC's website at www.sec.gov. The forward-looking statements in this presentation speak only as of the date of the presentation. Amphastar undertakes no obligation to revise or update information or any forward-looking statements in this presentation to reflect events or circumstances in the future, even if new information becomes available or if subsequent events cause our expectations to change.

You should not rely upon forward-looking statements as predictions of future events. Although our management believes that the expectations reflected in our forward-looking statements are reasonable, we cannot guarantee that the future results, levels of activity, performance or events and circumstances described in the forward-looking statements will be achieved or occur as forward-looking statements are inherently susceptible to uncertainty and changes in circumstances as with any projections or forecasts. Moreover, neither we, nor any other person, assume responsibility for the accuracy and completeness of the forward-looking statements. Any forward-looking statements made by us in this presentation speak only as of the date of this presentation, and we undertake no obligation to update any forward-looking statements for any reason after the date of this presentation, except as required by law.

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Fully Integrated Business Model

• Extensive in-house product development capabilities
• • Strong product development
  • State-of-the-artinstruments
  • Animal studies
  • Clinical research team
• Fully integrated back end manufacturing capabilities
• • API and starting materials
  • Key components
• Complete front end integration
• • Marketing
  • Distribution

Product

Development

API /Key

Components

Manufacturing

Finished

Product

Manufacturing

Marketing

Distribution

• Control over quality and compliance throughout the product development and manufacturing cycle

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Company Overview: Amphastar Facilities

Vertically integrated from R&D to clinical trials, manufacturing, marketing, and distribution

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Focus on Products With High Technical Barriers

Products with:

• Large markets
• High technical barriers to entry

Focused on:

• Injectables
• Inhalation
• Biosimilar
• Interchangeable

High Technical Barriers to Entry

• Scarcity of API requires unique synthetic or rDNA capabilities
• Characterization for complex molecules
• Immunogenicity studies for proteins and complex molecules
• Difficult or complex manufacturing processes
• Proprietary delivery technologies: PFS, MDI, IN, and sustained release
• Particle engineering from nm to μm
• Innovative formulations

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