Agenus (NASDAQ:AGEN) expects to begin enrolling patients in the next few months for a Phase 3 trial of its investigational immunotherapy combination BOT/BAL in early-stage colon cancer, executives said during an investor event.
The study, called ROBIN, will enroll approximately 850 patients with high-risk stage 2 or stage 3 microsatellite-stable colon cancer. It will compare treatment before surgery with botensilimab and balstilimab, known as BOT/BAL, against standard care.
Chief Commercial Officer Robin Taylor said the company chose the pre-surgery, or neoadjuvant, setting after results from the NEST and UNICORN studies. The company had previously studied the combination in metastatic disease.
Trial design and earlier results
ROBIN’s primary endpoint is event-free survival, a measure of how long patients remain free of specified events such as disease recurrence. Overall survival will be a key secondary endpoint, Taylor said.
Patients in the control group will undergo surgery followed by chemotherapy where appropriate. In both groups, postoperative chemotherapy decisions will be guided by tumor staging and treatment guidelines. Patients in the BOT/BAL group who have no detectable tumor in their surgical specimens and no affected lymph nodes would proceed to observation rather than chemotherapy, Taylor said.
Executives said they hope the approach will reduce recurrence while allowing some patients to receive less chemotherapy. The trial will also assess quality-of-life measures, including neuropathy associated with the chemotherapy drug oxaliplatin.
In the UNICORN study, Taylor said, the combination produced a 30% pathologic complete response rate among patients with microsatellite-stable tumors. He also said patients treated with the combination across the NEST and UNICORN studies had not experienced recurrences at median follow-up ranging from 19 to 32 months. Those results precede the larger randomized Phase 3 trial.
Taylor also discussed earlier metastatic data. In a Phase 1b group of 123 colorectal cancer patients without active liver metastases, he reported a 21% response rate and 33% survival at three years. The executives said safety and tolerability will be important in the early-stage population; ROBIN will use one dose of botensilimab before surgery, compared with two to four doses in the metastatic setting.
Financing and milestones
Zack Armen, Agenus’ vice president of corporate development and investor relations, linked the ROBIN timeline to a July private placement providing up to $340 million. The company received $85 million upfront, while a further $255 million depends on the exercise of two warrant tranches.
The first tranche would provide $85 million in gross proceeds if fully exercised and expires 30 days after Agenus publicly discloses that 50 patients have enrolled in ROBIN. Armen said the company expects to reach that milestone in the second quarter of 2027. He projected that the proceeds would extend the company’s cash runway through the first quarter of 2029.
An interim assessment of pathologic response in the first 100 patients will trigger the expiration period for the second warrant tranche, which could bring in another $170 million if fully exercised. Investors who do not exercise the first tranche will lose their second-tranche warrants, Armen said.
Agenus anticipates completing enrollment in the second half of 2028, with an interim event-free survival analysis in the second half of 2029 and a full readout roughly one year later. Taylor said the company is working to activate trial sites across several regions and expects the full study to be open by the middle of next year.
Taylor also estimated a U.S. addressable market of more than $7 billion for the treatment, based on an assumed course price of about $200,000. That estimate is the company’s projection; BOT/BAL remains under investigation for the condition.
About Agenus (NASDAQ:AGEN)
Agenus Inc is a biotechnology company focused on developing immunotherapies for the treatment of cancer. The company’s research programs are designed to activate and strengthen the immune system’s ability to recognize and attack tumors, with a focus on therapies that may be used across multiple cancer types.
Agenus develops a range of therapeutic approaches, including immune checkpoint inhibitors, cancer vaccines, bispecific antibodies and other antibody-based treatments. Its pipeline has included investigational therapies targeting immune-regulating pathways, as well as combination regimens intended to improve treatment responses and address resistance to existing cancer therapies.
The company was founded in 1994 as Antigenics and adopted the Agenus name in 2011.
