The glitazones seem to be a family of doomed anti-diabetes drugs.
In 2010, GlaxoSmithKline’s rosiglitazone was pulled from drug stores, as it was associated with a higher risk of heart attacks. Now, Takeda’s pioglitazone has been handed the same fate in India, over risks of urinary bladder cancer.
Earlier, ciglitazone and troglitazone were both abandoned over links to liver toxicity.
The development of ciglitazone was abandoned by Japan’s Takeda in the 1980s. And in 2000, Sankyo-discovery troglitazone, marketed by Warner-Lambert (a company now in the Pfizer-fold), was discontinued in the US.
The Indian research effort by Dr Reddy’s Labs on Balaglitazone did not see the light of day, as the glitazone class-effect took its toll.
Renewed debate
Pioglitazone’s troubled family history, and the Health Ministry’s decision, last week, to suspend its production and promotion, has rekindled a debate among doctors.
Questions are being asked on what prompted the suspension of pioglitazone, its impact on patients, and who would benefit from this action.
The total suspension of pioglitazone is “premature”, say doctors who prescribe the drug. Some of them were on their way back to India from the American Diabetes Association’s meeting in Chicago when they heard of the Government’s decision.
In India, pioglitazone is used in low doses. The concern overseas stems from high doses, of about 40 mg, used consistently in older patients, the doctors explain. They conceded that the drug is banned in Germany and France, but add that the US and European Union sell it with a risk warning.
Efficacy in India
In fact, the much-reviled Rosiglitazone is seeing a reversal, with recent studies taking a fresh look at the drug’s heart-friendliness, says a veteran diabetologist. Pioglitazone’s suspension is unfortunate, as it suits Indians, addressing their insulin resistance, says Vijay Panikar, a senior consultant endocrinologist with Mumbai’s Lilavati Hospital. The usage of gliptins and insulin as alternatives will now increase, he adds.
Another senior endocrinologist says that the Government should have restricted pioglitazone use and advised doctors to track side-effect complaints from patients. It is “faulty” to suspend a drug based on data from a European study, he says, adding that patients on pioglitazone have started approaching him for advice. Besides safety, patients will end up paying more, say doctors, with pioglitazone costing about Rs 6 for a tablet, whereas gliptins cost Rs 40.
However, C.M. Gulati, Editor of the drug journal MIMS , is not convinced that pioglitazone offers any added benefit compared to other drugs.
It does not have a unique mechanism and its working is similar to metformin, he says. Metformin is the first-level treatment of type II diabetes, and, according to Gulati, it is unclear whether pioglitazone works in patients in whom metformin fails to work.
“If the side effect was any less than malignancy, my reaction would have been different. Malignancy is unacceptable even if it occurs in one in a lakh patients,” he says.
Alternative benefits
Drug Controller G.N. Singh is convinced the drug needed to be suspended in the interest of patient safety.
Away from the debate, but linked to pioglitazone’s fate, are chemists.
Three boxes of pioglitazone, worth Rs 80,000, have been put in the ante-room, out of circulation, says a chemist in South Mumbai, responding to a customer’s query on the now-suspended medicine.