Aprogen's PMC-309 Shows Early Anticancer Activity in Phase 1 Trial, Advances to Higher Dose Testing
核心洞察
Aprogen (搜索)'s VISTA (搜索)-targeting antibody PMC-309 demonstrated early anticancer effects in phase 1a trials at low doses in patients with advanced solid tumors (搜索).
The Australian Safety Review Committee unanimously approved the 2mg/kg dose as safe, with patients showing only mild cytokine release symptoms and no other side effects.
The company plans to advance to 4mg/kg dosing and initiate combination trials with Merck (搜索)'s Keytruda in phase 1b, with potential for early technology transfer to Merck.
Aprogen (搜索), a South Korean antibody drug developer, has reported promising early results from its phase 1 clinical trial of PMC-309, a first-in-class immune checkpoint inhibitor targeting the VISTA (搜索) protein. The company announced that patients receiving the experimental cancer treatment showed anticancer effects even at low doses, prompting advancement to higher dose testing.
Safety Profile Supports Dose Escalation
The Australian Safety Review Committee unanimously approved the safety profile of PMC-309 at a 2mg/kg dose following evaluation of clinical results from patients with pleural mesothelioma (搜索), vulvar melanoma (搜索), and colorectal adenocarcinoma (搜索). According to Aprogen (搜索), patients experienced only mild cytokine release symptoms classified as grade 1, with no other adverse effects observed.
"We expect better anticancer effects in future medications," an Aprogen (搜索) official stated, adding that the company anticipates "more positive results from the next step of administering 4 mg of PMC-309 per kg of patient weight."
Novel VISTA-Targeting Mechanism
PMC-309 represents a new therapeutic approach as a first-in-class antibody that binds to VISTA (搜索) (V-domain Ig suppressor of T cell activation), an immune checkpoint regulatory protein present on various immune cells including myeloid-derived suppressor cells (MDSC), regulatory T cells (Tregs), and M2 macrophages. By targeting VISTA, the antibody aims to enhance immune T-cell activity against cancer cells.
The ongoing Australian clinical trial, supported by the government and conducted across multiple local hospitals, involves 67 patients and is structured in two phases. Phase 1a focuses on PMC-309 monotherapy in patients with advanced or metastatic solid cancers, while phase 1b will evaluate combination therapy with Merck (搜索)'s Keytruda (pembrolizumab).
Partnership with Merck Advances Combination Strategy
Under an agreement with Merck (搜索), the pharmaceutical giant is providing Keytruda at no cost for the combination clinical trials. The phase 1a portion involves dose escalation from low to high doses to establish the appropriate therapeutic concentration, while phase 1b will assess the efficacy of the PMC-309 and Keytruda combination.
"The positive effect of reducing cancer in cancer patients has already begun to be confirmed at the low-dose administration stage, and we expect the cancer effect to be significant if it is increased to a medium dose," an Aprogen (搜索) official explained. The company indicated that combination trials with Keytruda will commence once expected effects are observed at medium doses.
Technology Transfer Potential
Aprogen (搜索) has expressed optimism about the potential for early technology transfer to Merck (搜索) if the combination therapy proves effective in phase 1b trials. The company noted that positive clinical results emerged faster than anticipated.
"I didn't expect good news about the PMC-309 clinical trial to come out so quickly," an Aprogen (搜索) official commented. "If the effect of co-administration of Keytruda is confirmed, we will immediately begin overseas technology transfer."
The PMC-309 program originated from a technology transfer agreement with PharmAbcine (搜索), with Aprogen (搜索) securing exclusive development and commercialization rights for the VISTA (搜索)-targeting antibody.