A Mumbai-based tuberculosis survivor along with an advocacy group for HIV, Delhi Network of Positive People, has filed a pre-grant patent opposition with the Indian Patent office in Kolkata against a French pharmaceutical giant’s application for patents of drugs to prevent TB.
The pharmaceutical, Sanofi, had applied for patent in 2016 on a combination of rifapentine and isoniazid formulation for adults, and on a child-friendly water-dispersible formulation of these drugs for young children.
A standard TB preventive therapy involves isoniazid regimen for six months or more. Newer studies have shown a combination of isoniazid and rifapentine to be more effective – with lesser liver toxicity and a much shorter treatment duration of three months. In June 2019, the World Health Organisation also updated its guidelines to include the regimen for preventive therapy.
Isoniazid was approved and was available in market in 1952, while rifapentine in 1998. “Sanofi’s patent claims are not a new invention, but simply the combination of two existing drugs,” said activist Ganesh Acharya, who has opposed the patent application. The activist has argued that such a patent claim will hinder generic drugs from getting manufactured in India, forcing patients here to rely on costlier medicines.
Earlier this year, Sanofi had announced a cut in rifapentine prices by 66 per cent. Rifapentine currently cost $15 (Rs 1,070) for full course of 12 weeks. Even then, Acharya said, the cost remains too high for the huge latent TB population in India.
India, that holds the largest TB burden globally, has an estimated 40 per cent of its population infected by latent TB.
People living with HIV are twenty times more likely to get TB infection than the normal population. Preventive therapy for such patients becomes important. “Treating TB infection is a critical cog in the wheel to end AIDS. The Indian Patent Office should speedily reject Sanofi’s attempt to patent 3HP-a combination of two old TB drugs. We cannot afford to allow frivolous patents to block generic competition that could further lower prices for improved TB prevention for children and adults,” said Jai Prakash, president of Delhi Network of Positive People.
The French pharmaceutical company got a US FDA approval of Priftin (brand name for rifapentine) in 2014. It wanted to patent the fixed dose combination of rifapentine and isoniazid in India.
US-based organisation Treatment Action Group (TAG) has hailed the patent opposition move. In a statement TAG said, “Granting patents on these combinations could limit the regimen’s availability and affordability by blocking access to generic competition until 2033/2034.”
When contacted, Sanofi spokesperson said she was not aware of the patent opposition. An e-mail response on this was awaited at the time of going to press.
Globally, WHO data shows one-fourth of population is infected by latent TB bacteria. In 2017, around 1.6 million people died due to the infectious disease. India has set target of 2025 to end TB epidemic. The India TB Report, 2019, states the country has TB incidence of 27 lakh, but in 2018 only 21.5 lakh cases could be notified.