SANTIAGO, Chile — A team of Chilean scientists has taken a significant step in the fight against one of the deadliest forms of skin cancer, after the first results in humans of the therapeutic vaccine TRIMELVax showed encouraging signs against advanced melanoma. The development, led by biotechnology company Oncobiomed in partnership with the University of Chile, offers new hope for patients who no longer respond to standard treatments.
The Phase I clinical trial, published in the scientific journal British Journal of Cancer, enrolled 17 patients with metastatic melanoma treated at Hospital del Salvador in Santiago. All of them had seen their disease progress despite receiving first-line immunotherapy, a scenario the researchers themselves describe as leaving few remaining treatment options.
What sets TRIMELVax apart is its distinctly local origin. The vaccine combines heat-shocked melanoma tumor cell extracts with a natural adjuvant derived from hemocyanin taken from the loco (Concholepas concholepas), a marine snail native to Chile's coast and sometimes referred to as Chilean abalone. That combination is designed to more strongly activate the immune system so it can recognize and attack cancer cells, even in so-called "cold tumors," which typically evade immune surveillance.
The preliminary results were promising. Thirteen of the 17 patients completed the full four-dose schedule, administered on days 0, 28, 56 and 84. One patient experienced regression of lung metastases, while six others achieved disease stabilization, translating into a disease-control rate of roughly 41 percent. Median overall survival reached 14 months, a figure the team considers favorable within a group of patients who had few options left.
On safety, the study's primary objective, adverse effects were mostly mild to moderate, including fatigue, injection-site pain and flu-like symptoms, and no patient required hospitalization as a result of the treatment.
Professor Flavio Salazar-Onfray, who led the invention of the technology at the University of Chile's School of Medicine, said all of the vaccine's components "were discovered, designed and produced in the country," confirming that Chilean science can carry a treatment the full distance, from the laboratory to the patient.
The study also detected concrete immunological signals, including an increase in active cytotoxic T cells in the blood of treated patients, evidence that their bodies were responding to the vaccine. In addition, some patients who had stopped responding to anti-PD-1 immunotherapy managed to stabilize their disease after resuming that treatment following TRIMELVax, a clue researchers want to explore further.
The researchers, also led by oncologist Roberto Estay of Hospital del Salvador, caution that these are preliminary results drawn from a small sample, typical of an early research phase. Even so, the team is already planning its next step: building new laboratories certified by Chile's Institute of Public Health (Instituto de Salud Pública) and moving toward larger-scale clinical trials to confirm the treatment's efficacy.
For Chile, the milestone extends beyond medicine. TRIMELVax is one of the few biomedical technologies developed entirely within the country to make the leap from preclinical research to testing in real patients inside a public hospital, a path the scientists themselves describe as uncommon in the region. If upcoming trials confirm the signals observed so far, a marine creature from Chile's coast could become a global ally against one of the most aggressive cancers that exist.
