These drugs are undergoing study because a suitable dose and schedule has been found in Phase I trials. Phase I studies are trying to establish the drugs' effectiveness, usually in a wide range of tumor types. Several drugs already show promise against certain types of cancer, but this information is very preliminary.
Gemcitabine (difluorodeoxycytidine) is an antimetabolite introduced by Lilly Laboratories. It has shown encouraging activity—20 percent or more responses— in lung, ovarian and breast cancers. Some patients with pancreatic cancer have also shown improvement, although objective responses will likely not exceed 10 percent of patients even when they have been given no treatment before.
The toxicity profile is quite favorable. The drug has mild effects on the bone marrow . Short-term skin rashes and flu-like symptoms are the most commonly observed side effects.
Mitoguazone (Methyl-GAG, MGBG) is an old investigational drug. It had shown activity against malignant lymphomas and Hodgkin's disease, as well as some squamous cancers, but with considerable toxic effects to many organ systems. Its unique mechanism of action and the likelihood that new schedules or drug combinations will prove useful have piqued interest in re-assessing its role.
Oxaliplatin is a platinum derivative that has had all its initial studies in France. It has no toxic effects on the kidney and causes minimal bone marrow depression. The only troublesome toxicity has been numbness and
