KAHR Bio Reports Positive Phase 2 Results for DSP107 with anti-PD-L1 in Colorectal Cancer

In a significant advancement in cancer treatment, KAHR, an Israel-based clinical-stage biotechnology company, has unveiled promising results from its Phase 2 study of DSP107 combined with atezolizumab in patients with third-line microsatellite stable metastatic colorectal cancer (MSS-CRC). These findings were shared at the prestigious American Society of Clinical Oncology (ASCO) 2025 Annual Meeting, held in Chicago, Illinois.

DSP107 is a pioneering bi-specific 4-1BB T-cell engager that aims to enhance both innate and adaptive immunity against solid tumors. The combination of DSP107 and atezolizumab, a PD-L1 cancer immunotherapy, has demonstrated significant anti-tumor activity and prolonged survival rates, even among patients with challenging liver metastases. This promising therapy might pave the way for new treatment options that are not only effective but also have a favorable safety profile compared to traditional chemotherapy.

Colorectal cancer remains the second most common cause of cancer-related deaths globally, primarily due to its characterization as a "cold" tumor that generally fails to trigger a robust immune response. As highlighted by Dr. Anwaar Saeed, an Associate Professor at the University of Pittsburgh Medical Center, the combination therapy has shown durable effects in MSS-CRC patients, achieving longer median survival times compared to existing treatment standards. Importantly, patients exhibited good tolerance to the treatment, avoiding the severe side effects commonly associated with advanced chemotherapy.

The study's dose expansion cohort was an open-label, multi-center trial that involved administering 10 mg/kg DSP107 weekly and 1200 mg of atezolizumab every three weeks to patients until their disease progressed. The primary goal was to assess the safety and tolerability of this combination, with a secondary focus on evaluating its preliminary efficacy.

The data revealed that DSP107, both as a monotherapy and in combination with atezolizumab, was well-tolerated, with no dose-limiting toxicities observed. While the median overall survival (OS) for patients receiving only DSP107 was recorded at 8.1 months, those who underwent combination therapy reached a median OS of 17 months. Remarkably, disease control was achieved in 21% of patients on monotherapy and 62% of those receiving the combination.

One patient notably achieved a complete response lasting over two and a half years, while another experienced a significant 86% reduction in target lesions, with the disappearance of pulmonary and hepatic metastases after more than 16 months. Analyzing baseline tumor biopsies revealed high levels of CD47 expression, the target for DSP107, in all samples collected from liver metastases.

KAHR's Chief Executive Officer, Yaron Pereg, expressed optimism regarding these findings, noting that the combination of DSP107 with atezolizumab showed objective responses and extended survival in patients with third-line MSS-CRC. The company is preparing to launch a Phase 2b randomized, controlled study to further validate these encouraging results. Additionally, data from a Phase 2 dose expansion trial in non-small cell lung cancer (NSCLC) is anticipated in 2026.

DSP107 capitalizes on CD47 overexpression to act as a tumor anchor, attracting and activating adaptive immune cells, especially cancer-targeting CD8 T-cells. This approach is particularly significant in colorectal cancer, where a majority of metastatic cases involve liver metastases that express CD47 in response to conventional treatments. Unlike previous immunotherapy efforts that failed due to insufficient immune cell presence in tumors, DSP107 leverages CD47 expression to drive immune cells into the tumor environment, offering a holistic anti-cancer response.

MSS-CRC is a subtype of colorectal cancer characterized by stable microsatellite regions within the genome, making it less responsive to immunotherapy and more challenging to treat. Standard treatments often involve chemotherapy and targeted therapies, but DSP107's unique mechanism offers potential for improved outcomes in this difficult-to-treat patient group.