Original sentence: If a new, costly therapy that works on tumor blood vessels causes two kinds of cancer to go into remission, is it justified as an expense in a third kind of cancer, before this has specifically been proven
Edited sentence: However insurance companies are reluctant to take on the job of funding such treatments, preferrring instead to take the safer route of awaiting the results of clininal testing and leaving the funding of such trials to the manufacturer seeking a licence.Some people are willing to take their chances to gamble their health on the success of new drugs or old drugs in new situations which may not yet have been fully tested in clinical trials