Safety worries cloud promise of experimental cancer drugs

New York

A NEW wave of experimental cancer drugs that directly recruit the immune system's powerful T cells are proving to be immensely effective weapons against tumours, potentially transforming the US$100 billion global market for drugs that fight the disease.

But top oncology researchers are concerned about the two emerging technologies, citing dangers seen repeatedly in clinical trials including the potentially fatal build-up of toxic debris from killed tumour cells and damage to healthy tissue. Such side effects could block regulatory approval if they aren't controlled, researchers and drug company executives said in interviews with Reuters.