In placebo limbo?
By Julie Singh | 08 Feb 2002
1
Mumbai:
Two parallel studies conducted by the National Institute
of Pharmaceutical Education and Research (NIPER), Chandigarh,
and LM College of Pharmacy, Ahmedabad, have drawn up the
conclusion that most multi-drug pills against tuberculosis
marketed in the country may not be as effective as they
claim.
The findings, which appeared in The International Journal of Pharmaceutics, seem to have stirred up a controversy among leading anti-TB drug-makers here.
Multi-drug tablets, containing rifampicin, isoniazid, pyrazinamide and ethambutol in varying strengths, are widely recommended for the treatment of TB. The researchers suggest that a poor intake of rifampicin, the lead drug in these combinations, could be one of the contributing reasons for the frequent drug therapy failure among many TB patients.
The decreased absorption of rifampicin is due to the disintegration of rifampicin in the acid medium of the stomach. The decomposition was found almost two times more in presence of isoniazid, another major drug in the combination pill.
This, according to the studies, could explain why many therapeutic regimens, including the intensive direct observation therapy short-course (DOTS) against the disease, fail to bring in intended results in India. DOTS has been proved a success story elsewhere in the world.
Up until now the poor response to the tuberculosis therapy has usually been attributed to patients non-complaince. Patients often miss dosages, drop out or even discontinue during the months-long treatment period.
But most TB drug manufacturers vehemently dispute the conclusions. "Our formulations," one of them says, "are trialled in World Health Organisation-recognised facilities. It has been proven well that they are as effective as they are expected to be."
Says a senior scientist with a leading Mumbai-based pharmaceutical company: "We have developed the process technology to forego the possible disintegration, if any at all, of the drug [rifampicin] years ago. Now we need more studies to verify these academic observations before jumping into conclusions."
According to experts, the stability of rifampicin in combination therapies has always been under question. "And the drug firms are well aware of this, too. But they hardly do anything to sort it out. Now more skeletons will tumble out of the cupboard," says a quality-control official with a multinational company.
The Rs 347-crore tuberculostatics pie is shared by around 50 big and small-time players. Lupin Laboratories leads the market with a major 41-per cent share. This is followed by Novartis India (10.7 per cent), Macleods Pharma (6.8), Cadila Pharma (6.4), Wockhardt-Merind (5.9 per cent) and others.
The findings, which appeared in The International Journal of Pharmaceutics, seem to have stirred up a controversy among leading anti-TB drug-makers here.
Multi-drug tablets, containing rifampicin, isoniazid, pyrazinamide and ethambutol in varying strengths, are widely recommended for the treatment of TB. The researchers suggest that a poor intake of rifampicin, the lead drug in these combinations, could be one of the contributing reasons for the frequent drug therapy failure among many TB patients.
The decreased absorption of rifampicin is due to the disintegration of rifampicin in the acid medium of the stomach. The decomposition was found almost two times more in presence of isoniazid, another major drug in the combination pill.
This, according to the studies, could explain why many therapeutic regimens, including the intensive direct observation therapy short-course (DOTS) against the disease, fail to bring in intended results in India. DOTS has been proved a success story elsewhere in the world.
Up until now the poor response to the tuberculosis therapy has usually been attributed to patients non-complaince. Patients often miss dosages, drop out or even discontinue during the months-long treatment period.
But most TB drug manufacturers vehemently dispute the conclusions. "Our formulations," one of them says, "are trialled in World Health Organisation-recognised facilities. It has been proven well that they are as effective as they are expected to be."
Says a senior scientist with a leading Mumbai-based pharmaceutical company: "We have developed the process technology to forego the possible disintegration, if any at all, of the drug [rifampicin] years ago. Now we need more studies to verify these academic observations before jumping into conclusions."
According to experts, the stability of rifampicin in combination therapies has always been under question. "And the drug firms are well aware of this, too. But they hardly do anything to sort it out. Now more skeletons will tumble out of the cupboard," says a quality-control official with a multinational company.
The Rs 347-crore tuberculostatics pie is shared by around 50 big and small-time players. Lupin Laboratories leads the market with a major 41-per cent share. This is followed by Novartis India (10.7 per cent), Macleods Pharma (6.8), Cadila Pharma (6.4), Wockhardt-Merind (5.9 per cent) and others.
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