Pinotbio, a local biotech specializing in antibody-drug conjugate (ADC) platforms, said Tuesday that it has completed the phase 1a clinical trial for its targeted cancer therapy, NTX-301, in the U.S.

The drug, designed to inhibit the activity of DNA methyltransferase 1 (DNMT1), has shown promising results in halting the growth of cancer cells.

The trial focused on patients with hematologic malignancies, particularly those with Myelodysplastic Syndromes (MDS) and Acute Myeloid Leukemia (AML) who had no other treatment options.

Using a 3+3 design, the trial gradually increased the dosage from 2mg to a maximum of 24mg across 12 patients.

The results showed no dose-limiting toxicities (DLTs) or significant adverse reactions, even at the highest dose.

The company said the drug's safety and tolerability were demonstrated by the absence of common side effects of existing DNMT1 inhibitors, including neutropenia.

In addition to its safety profile, NTX-301 showed efficacy in some patients, achieving near-complete remission and CRi (Complete Remission with incomplete blood count recovery).

Despite the poor prognosis associated with MDS and AML, where the expected survival is typically 1.3 to two months, many patients in the trial survived beyond eight weeks, with some continuing treatment for up to eight months.

Based on these findings, Pinot Bio plans to commence phase 1b/2a trials immediately next month, aiming to explore the drug’s potential further.

“The five-year survival rate for elderly AML patients, who are not candidates for hematopoietic stem cell transplantation, is alarmingly low,” Pinotbio CEO Jung Doo-young said. “Despite the high unmet medical needs for elderly MDS/AML patients, there has been no significant advancement in standard treatments for decades.”

Jung added that NTX-301 could offer a viable alternative for these patients, and the company is committed to advancing its clinical development.