Catalyst Pharmaceuticals Reports Fourth Quarter and Full Year 2021 Financial Results and Provides Business Update Total 2021 Revenues Increased Approximately 18% YoY to $141 Million Strong 2022 Revenue Growth Expected, S

Catalyst Pharmaceuticals Reports Fourth Quarter and Full Year 2021 Financial Results and Provides Business Update

Total 2021 Revenues Increased Approximately 18% YoY to $141 Million

Strong 2022 Revenue Growth Expected, Supported by FIRDAPSE Orphan Drug Exclusivity

New Patent Issuances Strengthens FIRDAPSE Long-Term Commercial Potential to 2034

Actively Pursuing Opportunities to Diversify Commercial and Development Portfolio

Strong Cash and Investments Position of $191 Million and No Funded Debt

Company to Host a Conference Call and Webcast on March 17, 2022, at 8:30 AM ET

CORAL GABLES, Fla., March 16, 2022 Catalyst Pharmaceuticals,

Inc. ( Catalyst ) (Nasdaq: CPRX), a commercial-stage biopharmaceutical company focused on in-licensing, developing, and commercializing novel medicines for patients living with rare diseases,

today reported financial results for the fourth quarter and full year 2021 and provided a corporate update.

financial performance during 2021, marked by our sustained focus on commercial and operational execution, which created a sizeable foundation as we continue to execute on our business strategy and invest in our long-term growth,

said Patrick J. McEnany, Chairman and Chief Executive Officer of Catalyst. We entered 2022 with great momentum, having received affirmation of the orphan drug exclusivity for FIRDAPSE coupled with the issuance of three new patents

directed to the treatment of patients suffering from LEMS, further reinforcing and diversifying our existing patent exclusivity to 2034. These important milestones significantly reinforce the product s commercial durability and are defining

inflection points supporting the Company s continued growth. We believe we are well-positioned to build upon our success and are optimistic about the future of the Company as we diligently pursue opportunities to diversify our commercial and

development portfolio, which aligns with our core mission to deliver value to our patients, healthcare providers, and shareholders.

Fourth Quarter and Full Year 2021 Financial

Total revenues: Total revenue in the fourth quarter of 2021 was $38 million, compared to total fourth quarter 2020

revenues of $31 million, representing an increase of approximately 24% year-over-year. The full year 2021 total revenues were $141 million, compared to total revenues of $119 million for 2020, representing an increase of approximately

Total product revenue, net: Total product revenue, net in the fourth quarter of 2021

was $38 million, compared to $31 million for the fourth quarter of 2020, representing an increase of approximately 24% year-over-year. Full year 2021 product revenue, net was $138 million, compared to $119

million for the full year 2020, representing an increase of approximately 16% year-over-year.

Operating income: Operating income for the fourth quarter of 2021

was $13 million, compared to $9 million in the fourth quarter of 2020. Full year 2021 operating income was $52 million, compared to $41 million for the full year 2020.

Research and development expenses: In the fourth quarter of 2021, research and development expenses

were $5 million, compared to $4 million in the fourth quarter of 2020. Research and development expenses for the full year 2021 were $17 million, compared to $16 million for the full year

Selling, general, and administrative expenses: Selling, general, and administrative expenses for the fourth quarter of

both 2021 and 2020 were $13 million. Selling, general, and administrative expenses for full year 2021 were $50 million, compared to $44 million for full year of 2020.

GAAP Net Income for the fourth quarter of 2021 was $9 million ($0.09 per basic and diluted share), compared to $11 million

($0.11 per basic and diluted share) for the fourth quarter of 2020. Net income for full year 2021 was $39 million ($0.38 per basic and $0.37 per diluted share), compared to full year 2020 net income of $75 million ($0.72 per basic and

$0.71 per diluted share). Net income for the fourth quarter of 2020 benefitted from $3 million of income tax benefit. Net income for full year 2020 benefitted from $33 million of income tax benefit, including the one-time recording of an approximately $31.6 million deferred tax asset upon reversal of a valuation allowance.

Non-GAAP Financial Measures

Non-GAAP1 net income for the fourth quarter of

2021 was $14 million ($0.14 per basic and $0.13 per diluted share), which excludes from GAAP net income of $9 million (i) stock-based compensation expense of $1 million, (ii) depreciation of $33 thousand, and

(iii) the provision for income taxes of $4 million. This compares to non-GAAP1 net income for the fourth quarter of 2020 of $10 million

($0.10 per basic and diluted share), which excludes from GAAP net income of $11 million (i) stock-based compensation expense of $1 million, (ii) depreciation of $19 thousand, and (iii) a benefit for income taxes of

The non-GAAP financial measure in this press release excludes from the calculation of

net income (i) the expense associated with non-cash, stock-based compensation, (ii) depreciation expense, and (iii) the (benefit) provision for income taxes.

Non-GAAP income per share is calculated by dividing non-GAAP income by the weighted average common shares outstanding.

Non-GAAP1 net income for the full year 2021 was $59 million ($0.57 per basic and $0.55 per diluted share), which excludes from GAAP net income of $39 million (i) stock-based compensation expense

of $6 million, (ii) depreciation of $192 thousand, and (iii) the provision for income taxes of $13 million. This compares to non-GAAP1

net income for full year 2020 of $48 million ($0.47 per basic and $0.45 per diluted share), which excludes from GAAP net income of $75 million (i) stock-based compensation expense of $6 million, (ii) depreciation of

$92 thousand, and (iii) a benefit for income taxes of $33 million, as the Company recorded the deferred tax asset during the third quarter of 2020. A tabular presentation of non-GAAP1 net income for the three months and full year ended December 31, 2021 and 2020 is included below.

More detailed financial information and analysis can be found in the Company s Annual Report on Form

10-K for the fiscal year ended December 31, 2021, which was filed with the Securities and Exchange Commission ( SEC ) on March 16, 2022.

Cash and investments were $191 million as of December 31, 2021, with no funded debt.

Share repurchase program: The Company implemented a share repurchase program in March 2021. As of December 31, 2021, the Company

had repurchased 2.2 million shares of Catalyst common stock in the open market, at an average price of $5.47 per share, for a total purchase price of $12.1 million.

2022 Financial Guidance: The Company forecasts full year 2022 total revenues to be in the range of between $195 million and

$205 million, representing a 38% 45% increase in total revenues as compared to 2021, with cash operating expenses for the full year 2022 expected to be in the range of $65 million to $70 million. Key guidance assumptions included

in these forecasts reflect a continued recovery in macroeconomic and healthcare activity throughout 2022 as it relates to the current COVID-19 environment.

Conference Call & Webcast Details

The Company will host a conference call and webcast on Thursday, March 17, 2022, at 8:30 AM ET to discuss the financial results and

provide a business update.

US/Canada Dial-in Number: (877) 407-8912

International Dial-in Number: (201) 689-8059

A webcast and accompanying materials will be accessible under the investor section on the

Company s website at www.catalystpharma.com. A replay of the webcast will be available on the Catalyst website for 30 days following the date of the event.

About Catalyst Pharmaceuticals

Catalyst Pharmaceuticals is a commercial-stage biopharmaceutical company focused on in-licensing,

developing, and commercializing novel medicines for patients living with rare diseases. With exceptional patient focus, Catalyst is committed to developing a robust pipeline of cutting-edge, best-in-class medicines for rare diseases. Catalyst s New Drug Application for FIRDAPSE (amifampridine) Tablets 10 mg for the treatment of

adults with Lambert-Eaton myasthenic syndrome ( LEMS ) was approved in 2018 by the U.S. Food & Drug Administration ( FDA ), and FIRDAPSE is commercially available in the United States as a treatment

for adults with LEMS. Further, Canada s national healthcare regulatory agency, Health Canada, has approved the use of FIRDAPSE for the treatment of adult patients in Canada with LEMS.

Forward-Looking Statements

This press release contains forward-looking statements. Forward-looking statements involve known and unknown risks and uncertainties, which may

cause Catalyst s actual results in future periods to differ materially from forecasted results. A number of factors, including (i) the continuing effect of the COVID-19 pandemic on Catalyst s

net product revenues and net income, (ii) Catalyst s ability to locate and acquire new product candidates through acquisition or in-licensing, (iii) Catalyst s ability to successfully

develop any new product candidates acquired or in-licensed, (iv) whether Catalyst s total revenue forecast for 2022 will prove to be accurate, and (v) those factors described in Catalyst s

Annual Report on Form 10-K for the fiscal year 2021 and Catalyst s other filings with the U.S. Securities and Exchange Commission ( SEC ), could adversely affect Catalyst. Copies of

Catalyst s filings with the SEC are available from the SEC, may be found on Catalyst s website, or may be obtained upon request from Catalyst. Catalyst does not undertake any obligation to update the information

contained herein, which speaks only as of this date.

Source: Catalyst Pharmaceuticals, Inc.

Catalyst Pharmaceuticals, Inc.

CATALYST PHARMACEUTICALS, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

(in thousands, except share data)

CATALYST PHARMACEUTICALS, INC.

RECONCILIATION OF NON-GAAP METRICS (unaudited)

(in thousands, except share data)

CATALYST PHARMACEUTICALS, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS