Topline results from a Phase 2a clinical trial show that GLPG1690 successfully halted the worsening of idiopathic pulmonary fibrosis (IPF) in patients, its developer, the Belgian biotechnology firm Galapagos, announced.

A double-blind, randomized, placebo-controlled trial, FLORA (NCT02738801) explored the effects of GLPG1690 as a once-a-day oral treatment in about 23 IPF patients. Within 12 weeks, those treated showed significant improvement in lung function, assessed through forced vital capacity (FVC), a measure of how much air can be forcibly expelled from the lungs in one deep breath.

Patients given GLPG1690 showed a FVC increase of 8 mL from baseline, or before treatment. In contrast, as is expected in patients with the condition, IPF participants who received placebo showed a decline in their FVC (87 mL).

“The stabilization of FVC over 12 weeks upon GLPG1690 treatment is a major milestone in IPF, where, by way of reference, the currently approved treatments show a decrease of approximately 30 mL over the same treatment period,” Piet Wigerinck, chief scientific officer of Galapagos, said in a press release.

GLPG1690 is a first-of-its-kind autotaxin inhibitor with the potential to treat IPF. Autotaxin is an enzyme largely present in the brain, kidneys, testis and lymph nodes. It converts a factor called lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA) in the blood; LPA is known to worsen lung fibrosis in IPF, leading to increasing shortness of breath in patients.

By inhibiting or blocking autotaxin, GLPG1690 can improve lung function in patients and slow a worsening of the disease.

IPF patients who participated in the FLORA study also showed clear reductions in serum levels of LPA18:2 after receiving treatement with GLPG1690. LPA18:2 is a biological marker that helps measure the degree of autotaxin inhibition in the blood.

Furthermore, study participants not only tolerated GLPG1690 well, but the rate of treatment discontinuation due to side effects and the rate of serious side effects were similar between participants receiving placebo and those receiving the drug.

Functional respiratory imaging (FRI), which are imaging tests that can visualize lung function in 3-D and considerable detail, further confirmed the FVC improvement in patients receiving the drug.

“Galapagos’ results with GLPG1690 are extremely exciting and exceed those of previous studies. This brings hope to patients with idiopathic pulmonary fibrosis that new effective treatment may be on the horizon,” Toby Maher, a professor of Interstitial Lung Disease at Imperial College London and consultant physician at Royal Brompton Hospital, London, one of the trial’s test sites.

“Importantly, some patients even showed an increase of lung function within only 12 weeks of treatment, and the drug was well tolerated. The results from FLORA beg the question how patients will fare with longer treatment. I urge Galapagos and the IPF community to progress to the next phase of clinical trials as rapidly as possible,” Maher added.

In March 2016, Galapagos reviewed preclinical study results on GLPG1690 at the 251^st American Chemical Society National Meeting, held in San Diego, in a presentation titled “Discovery of GLPG1690: a first-in-class autotaxin inhibitor in clinical development for the treatment of idiopathic pulmonary fibrosis.”

The company plans to advance the development of GLPG1690 into a late-stage trial, and is discussing the trial design with regulatory agencies.