Pliant Therapeutics Halts Lead Drug Trial for Stiff Lung Tissues

Pliant Therapeutics, Inc. (Nasdaq: PLRX) has announced a voluntary pause in enrollment and dosing in its BEACON-IPF Phase 2b trial of bexotegrast in patients with idiopathic pulmonary fibrosis (IPF). The decision follows recommendations from the trial's independent Data Safety Monitoring Board (DSMB) after a prespecified data review. The DSMB's recommendation suggests a potential safety concern, although the specific reasons behind the pause are not yet known.

The DSMB's recommendation to pause the trial is a significant development for Pliant Therapeutics, as it raises questions about the safety and efficacy of bexotegrast, the company's lead product candidate. The pause in the trial could have implications for the company's financial outlook and its ability to raise additional funding, as investors may become cautious about the drug's development prospects.



Pliant Therapeutics' shares fell around 58% in aftermarket trading on Friday, February 7, 2025, according to SeekingAlpha. The immediate market response reflects investors' concerns about the potential impact of the trial pause on the company's future prospects. However, it is essential to note that the ultimate impact will depend on the findings from the data review and subsequent decisions regarding trial continuation.

The pause in the BEACON-IPF trial comes as Pliant Therapeutics was preparing to report interim data from the study in mid-2026. The company had previously reported positive data from a Phase 2a trial of bexotegrast in IPF, which showed that the drug was well-tolerated and demonstrated durable improvements in exploratory efficacy endpoints. The Phase 2b trial was designed to confirm these findings and potentially support the drug's approval for the treatment of IPF.



The decision to maintain trial blinding while pausing enrollment and dosing in the BEACON-IPF trial has several implications for the timeline, program viability, and financial outlook of Pliant Therapeutics. The pause in enrollment and dosing will likely result in delays in completing the trial, as new patients will not be added, and existing patients will not progress through the study as planned. The data review process may take some time, further extending the timeline. In the meantime, the trial will remain blinded, meaning that neither the investigators nor the participants will know the treatment assignments, which could slow down the decision-making process.

The outcome of the data review could range from a simple restart to major protocol amendments or, in a worst-case scenario, program termination. The DSMB's recommendation suggests a potential safety concern, which could lead to significant changes in the trial's design or even its discontinuation. The fact that currently enrolled patients will remain in the trial is a moderately encouraging sign, as complete trial terminations typically involve immediate discontinuation of all dosing. However, the uncertainty surrounding the DSMB's recommendation and the potential impact on the trial's future remains.

Extended trial delays could affect Pliant Therapeutics' cash runway and development timelines. The company had more than $400 million in cash reserves as of the third quarter of 2023, but any delays in the BEACON-IPF trial could potentially deplete these reserves more quickly than anticipated. The financial impact will depend on the duration of the pause, the need for additional resources to address any safety concerns, and the potential for additional funding requirements if the trial is modified or restarted.

In summary, Pliant Therapeutics' decision to pause its lead drug trial for stiff lung tissues raises concerns about the potential reasons behind the DSMB's recommendation and the impact on the company's future prospects. Investors will be watching closely as the company reviews the data and determines the best course of action moving forward. The ultimate impact on the company's financial outlook and ability to raise additional funding will depend on the findings from the data review and subsequent decisions regarding trial continuation.