As govt keeps out Tamiflu, Virenza hogs the counters

It can’t get more ironic than this. At a time when the government is odd at ease controlling the sale of key swine flu drug oseltamivir, sold under the brand name Tamiflu, another swine flu drug, zanamivir, has started hitting shop shelves with abandon.
Currently, oseltamivir and zanamivir are the only treatments available for swine flu.

So far, the government has made Tamiflu available only to authorised hospitals, in a bid to prevent its misuse and indiscriminate use, as well as hoarding and black marketing.
The government has been sourcing oseltamivir directly from its maker, Swiss pharma major Roche, which owns the brand Tamiflu, as well as from Hyderabad-based generics company Hetero Drugs.

Companies like Ranbaxy Laboratories, Cipla, Strides Arcolab and Natco Pharma are the other generic makers of oseltamivir.

The government has not considered zanamivir for introduction in India, though it is used for treating swine flu in several countries, on the ground that its safety has not been proven in children below 5 years and thus cannot be given to them. Also, zanamivir is administered through inhalation. On the other hand, oseltamivir can be given to children above six months and is administered orally.

However, about 10 days ago, Mumbai-based Cipla launched the generic version of zanamivir (brand name is Virenza) at retail chemists in Mumbai, Pune, Andhra Pradesh and Tamil Nadu. It is also available in a chemist store in New Delhi.

According to a source, who happens to be an official of the company, Virenza is priced at Rs 800 for one course, which consists of 20 capsules to be administered over five days (four per day). The price also includes the inhalation device.

Virenza had got the approval of Drugs Controller General of India on January 22, 2008 and was launched soon after, but its sales have not been encouraging.

British major GlaxoSmithKline (GSK) is the innovator company of zanamivir, whose brand is called Relenza.

Interestingly, while Virenza is available in several retail chemist outlets across Mumbai, Relenza is not, a member of the Retail Druggists and Chemists Association pointed out.
That’s because the government has still not placed orders for the drug with GSK, a company spokesperson said. “GSK India is still in discussion with the government to stock Relenza.”

A senior medical practitioner, who is also on the government appointed advisory panel for swine flu, expressed surprise when told that zanamivir was available in the open market. The reasons for which retail sale of oseltamivir is not allowed also hold for zanamivir, he said, adding, irrational use of either drug can lead to the virus becoming resistant to it. “If retail sale of oseltamivir is not allowed, how can it be allowed for zanamivir?”

In fact, both the drugs are known to have many side effects and thus need to be used under strict medical supervision. While oseltamivir is known to cause rashes, nausea, liver failure, etc, zanamivir’s side effects include diarrhoea, nausea, sinus inflammation and rashes, and can be a cause for concern in patients with asthma or chronic bronchitis since it is administered through inhalation.