New Delhi: The sale of drug combinations containing last-resort antibiotics is rising faster than overall antibiotics sales in India, health researchers have said in a study that also highlights the government's failure to stop the sale of irrational and unapproved antibiotic cocktails.

While total antibiotics sales in India rose 26 per cent over a four-year period, says the study, there was a 174 per cent increase in the sales of drug combinations containing antibiotics that should be used only after other medicines have failed.

Many of the so-called fixed-dose combinations of antibiotics have not been approved by the Central Drugs Standards Control Organisation, the country's apex drug regulatory agency, and should thus be considered illegal drugs, the researchers said.

Although the drug regulator had acknowledged the problem and banned dozens of fixed-dose combinations, including antibiotic combinations, last year, most of these drugs remain in the market with their companies getting the ban quashed in court.

The recent study, by British and Indian researchers, examined antibiotics sales between 2008 and 2012 and found that 75 (64 per cent) among 118 fixed-dose combinations of antibiotics sold in India lacked regulatory approval, while 43 (36 per cent) had the approval. The findings were published this week in the journal Lancet Global Health.

Only five of the 43 approved fixed-dose combinations have also been approved by drug regulators in Britain and America.

"The sales of antibiotics that require the most careful control and regulation are increasing at the fastest rate," Patricia McGettigan, a clinical pharmacologist at the Queen Mary University of London who led the study, said in a media release.

"Even worse, many (of these) formulations had never been approved by the national drug regulator."

The study has found that:

• Sales of fixed-dose combinations containing antibiotics that the World Health Organisation has classified as "key access" (which should be widely available) increased by about 20 per cent over the four-year period;

• Sales of fixed-dose combinations with antibiotics that the WHO has labelled "watch group" (which should be used restrictively for a small number of infections) grew at 73 per cent; and

• Sales of fixed-dose combinations containing antibiotics from the WHO's "reserve group" (last-resort antibiotics) grew by 174 per cent.

Among two-drug anti-microbial combinations unapproved by the drug regulator are ciprofloxacin-tinidazole, ceftriaxone-vancomycin, and norfloxacin-metronidazole. Some of the fixed-dose combinations containing "reserve group" antibiotics have regulatory approval.

"Even for the fixed-dose combinations approved by the regulator, we do not know the rationale for the approvals because there is no public access to the information or evidence underpinning those approvals," McGettigan told The Telegraph.

"From a transparency perspective, rigorous regulation would include making the supporting evidence and the rationale for decisions available for public scrutiny."

The researchers say their findings highlight the challenges India faces in curbing the growth of multi-drug-resistant bacteria, or superbugs, that can emerge through the widespread abuse of antibiotics.

McGettigan and her colleagues say the obvious practical steps are to ban the sale of unapproved fixed-dose combinations antibiotics and enforce the existing regulations to prevent unapproved and illegal drugs from reaching the market.

"The Indian government has been unsuccessful on both counts," the researchers wrote in their paper.

However, public health activists fighting for a ban on irrational fixed-dose combinations in India said the drug regulator had signalled the government's intention to ban fixed-dose combinations.

Delhi High Court, responding to multiple petitions from drug companies, had quashed a ban on certain fixed-dose combinations imposed by the drug regulator last year, but the government has appealed to the Supreme Court.

"We do see a momentum now from the drug regulator in pushing through the ban," said Sourirajan Srinivasan, a member of the All India Drug Action Network, a consortium of health activists and doctors that has joined the government in its petition seeking a ban.