MedPacto has applied for phase 2 clinical trials concerning the combined use of its Vactosertib and MSD’s Keytruda as a first-line therapy for non-small-cell lung carcinoma (NSCLC), to the Ministry of Food and Drug Safety.

Vactosertib is a drug candidate that selectively inhibits transforming growth factor-beta (TGF-β), a mechanism that inhibits the therapeutic effect of immunotherapy.

According to MedPacto, the company plans to confirm the safety and efficacy of the combination therapy by administering it to 55 programmed death-ligand 1 (PD-L1) positive NSCLC patients at four local medical institutions, including Samsung Medical Center.

Keytruda has shown significant therapeutic results in a group of NSCLC patients with 50 percent or more PD-L1 protein expression when used as first-line monotherapy. However, in the patient group with an expression rate of less than 50 percent, the drug has not exceeded the existing chemotherapy effect.

As the clinical trial targets patients with a PD-L1 expression rate of 1 percent or higher, the company expects it will be able to provide new treatment options to patients with low response rates.

“Unlike other combination clinical trials that are currently in progress, this trial aims to make the combination therapy into a first-line treatment for the indication,” a company official. “Since the trial is targeted for patients who have not received conventional treatment, we expect stable data generation and high response rate.

If this trial proves successful, the combination of the two treatments will open the possibility to lead the NSCLC treatment market, he added.