Putting Gleevec tablets in glycerin capsules raises serious concerns

By Jerry Call and Norman Scherzer

Last month we published a short article in our October Newsletter headlined "Life Rafter members find solution to Gleevec tablet nausea." We reported that several GIST patients who had switched from the original orange Gleevec capsules to the tablet form had experienced increased side effects, including nausea.

The article went on to cite a possible solution-namely, to put the Gleevec tablets inside empty glycerin capsules. The rationale was that this would allow the tablets to travel further down the gut before dissolving, bypassing sensitive regions where nausea arises. The source of this advice was said to be an oncology nurse and an oncologist.

We have since spoken to several people at Novartis who had concerns about our article, most noteworthy Dr. Bin Peng, MD, PhD, the Senior Clinical Pharmacokineticist in the Department of Clinical Pharmacology. Dr. Peng received his medical degree from Sun Yet-sen University of Medical Sciences in China. He completed his postdoc- fellowship in Manchester University, UK with Prof. Malcolm Rowland. He has authored and coauthored more than 50 papers and abstracts on clinical pharmacokinetics/ pharmacodynamics in the field of anticancer drugs. As a clinical pharmacokineticist, he has been involved in the first investigations of the pharmacokinetics/ pharmacodynamics of Glivec (STI571) in man.

Based upon Dr. Peng’s input we would like to withdraw our recommended solution. These are the reasons:

First, it is unknown if the solubility of the glycerin capsules would compare to that of the original orange Gleevec capsules.

Second, it is not known how placing the tablets into the capsules affects the solubility of the tablets. Our understanding is that the patient would probably take a pill cutter and cut the capsule in half. This may produce quite a different result than the original powdered form of Gleevec that went into the original orange capsules.

The bottom line is that we do not know how this suggested procedure would affect the absorption of the drug and hence affect the efficacy of the drug.

Given that most patients have reported that the increase in side effects accompanied by the switch from capsules to tablets resolves over time, it does not seem that this suggested procedure is worth the potential risks.