UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q For the quarterly period ended March 31, 2024 ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-39303 PLIANT THERAPEUTICS, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 47-4272481 (State or other jurisdiction of (I ...

Exhibit 99.1 Pliant Therapeutics Provides Corporate Update and Reports First Quarter 2024 Financial Results BEACON-IPF pivotal, adaptive Phase 2b/3 trial design implementation significantly accelerates bexotegrast development in IPF Data from completed 12 week Phase 2a imaging trial measuring bexotegrast's ef ect on total lung collagen and FVC in IPF patients expected in the coming weeks Regulatory clearance received for muscular dystrophy program PLN-101325, allowing conduct of a first-in-human Phase 1 cli ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 _____________________________________________ FORM 10-K _____________________________________________ (Mark One) x ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 OR ¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-39303 _________________ ...

Exhibit 99.1 Pliant Therapeutics Provides Corporate Update and Reports Fourth Quarter 2023 Financial Results Positive interim 12-week safety and ef icacy data reported from Phase 2a INTEGRIS-PSC trial in patients with PSC • Positive safety and efficacy data from 320 mg dose cohort of INTEGRIS-PSC Phase 2a trial in patients with primary sclerosing cholangitis (PSC). At a once-daily dose of 320 mg, bexotegrast was well tolerated over 12 weeks of treatment with no drug-related severe or serious adverse events. ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-39303 PLIANT THERAPEUTICS, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 47-4272481 (State or other jurisdiction o ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2023 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-39303 PLIANT THERAPEUTICS, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 47-4272481 (State or other jurisdiction of (I. ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-39303 PLIANT THERAPEUTICS, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 47-4272481 (State or other jurisdiction of (I ...

MARCH 2023 Disclaimers This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and growth 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 u ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 _____________________________________________ FORM 10-K _____________________________________________ (Mark One) x ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-39303 _________________ ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2022 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-39303 PLIANT THERAPEUTICS, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 47-4272481 (State or other jurisdiction o ...