Pliant Therapeutics’ anti-fibrotic drug seems to have engaged its target in a mid-stage lung disease clinical trial, which was enough to excite investors and push the biotech’s shares up.
But the company’s watchers will have to wait to see if the drug actually works to correct idiopathic pulmonary fibrosis, or IPF, as the trial is currently only examining whether PLN-74809 reaches its destination as planned. The biotech’s executives are waiting for longer term data to confirm the effect in patients, who experience scarring in the lungs that can make breathing difficult.
PLN-74809 appears to have reached areas of the lung that are highly scarred and engaged with the intended target, a protein called αvβ6. The trial’s patients across all four dosing levels achieved greater than 50% target engagement, according to a Tuesday press release.
Up to 98% target engagement was also seen in the trial. The interim results were confirmed through PET imaging scans.
Investors were clearly happy with the news, as the company’s shares shot up almost 15% to $22.21 as the markets opened Tuesday.
The data add to Pliant’s understanding of how PLN-74809 can address fibrosis and will inform dosing for the ongoing phase 2a study called Integris-IPF, said Pliant Therapeutics’ Chief Medical Officer Éric Lefebvre, M.D..
Since fibrosis is a chronic disease, the company noted that it can take years to determine the efficacy of a drug candidate and trials can be costly. PLN-74809 is therefore being examined using PET imaging and biomarkers, measurable substances in the body that can be used to suggest clinical effects in a disease.
This allows for a shorter evaluation as well as de-risks “Pliant’s programs by designing clinical trials that allow the company to show proof-of-mechanism in advance of clinical efficacy data,” according to the release.
Boiling that down, Pliant is aiming to show the therapy engages the target first while awaiting more thorough data that prove it actually works to correct the disease.
“We believe the high target engagement levels seen after the administration of just a single dose illustrate the potential of PLN-74809 to show a potent anti-fibrotic effect in our longer-term clinical trials,” said Lefebvre.
The therapy was well tolerated and no adverse events were reported.
Pliant emerged onto the public markets last year with a $144 million upsized IPO to propel PLN-74809 through the clinic. PLN-74809 is also being trialed in primary sclerosing cholangitis, an inflammatory liver condition. The biotech has partnered with Novartis on a treatment called PLN-1474 for nonalcoholic steatohepatitis, or NASH.