A common hypertension drug may be a secret weapon against cancer. Researchers at Dartmouth Cancer Center found that telmisartan, an everyday blood pressure medication, significantly boosts the effectiveness of olaparib — a targeted cancer drug — even in tumors that wouldn't normally respond to it. Two clinical trials are already underway to test the combination in prostate and ovarian cancer patients.
A widely used blood pressure medication may have a surprising second act in cancer care. Researchers at Dartmouth Cancer Center discovered that telmisartan — an angiotensin II receptor blocker (ARB) commonly prescribed for hypertension — dramatically enhances the cancer-fighting power of olaparib, a PARP inhibitor used to treat tumors with DNA repair defects (like those linked to BRCA mutations). The catch? Most cancers don't have those defects, limiting who can benefit from PARP inhibitors. Telmisartan could change that.
In preclinical studies, the drug combo increased DNA damage in cancer cells and triggered a stronger immune response by boosting type I interferons — signaling molecules that help the immune system hunt down tumors. Telmisartan also reduced PD-L1, a protein cancers use to evade immune detection. Notably, these effects were unique to telmisartan among other ARBs tested.
Key Takeaways:
Why it matters: Telmisartan is oral, inexpensive, safe, and well-tolerated — even in people without hypertension. If clinical trials confirm these results, it could rapidly expand the number of patients who benefit from PARP inhibitors and potentially help overcome drug resistance.
