ABC News | Grapefruit juice ups efficacy of cancer drug Times of India Sirolimus was the first of a series of drugs, known as mTOR inhibitors, that were developed to prevent rejection of transplanted organs but that also have anti-cancer effects. Patients who drank eight ounces a day of grapefruit juice increased their ... Study: Grapefruit Juice May Boost Anti-cancer Drug Grapefruit juice may help anti-cancer drugs to be more effective, say researchers Grapefruit Juice Could Help Cancer Patients Save Money |