Apart from India, the RDIF says Sputnik V will also be produced in Brazil, China and South Korea.
One person has died and more than 400 have been taken to hospital in southern India due to an unidentified infection that caused many to fall unconscious following seizures and nausea, according to a senior health department official.
The illness was detected on Saturday evening in Eluru, an ancient city in Andhra Pradesh state famous for its hand-woven products.
Since then, patients have experienced symptoms ranging from nausea and anxiety to loss of consciousness, doctors said.
Government and medical authorities in Andhra Pradesh said more than 200 people were discharged at the weekend and that tests had ruled out COVID-19, the disease caused by the novel coronavirus.
Further serological tests are under way.
Separately, India’s federal health ministry said on Monday it would send a team of three medical experts to investigate the outbreak, which it said has infected more than 300 children.
“The children reportedly suffered from dizziness, fainting spells, headache and vomiting,” the ministry said, adding that a door-to-door survey was also under way.
Meanwhile, Indian authorities on Tuesday said they are investigating if organochlorines used as pesticides or in mosquito control caused the outbreak.
Federal lawmaker GVL Narasimha Rao, who is from the state, said on Twitter that he had spoken with government medical experts and that the “most likely cause is poisonous organochlorine substances”.
“It is one of the possibilities,” said Geeta Prasadini, a public health director in Andhra Pradesh state, adding they were awaiting test reports to ascertain the cause.
She said no new serious cases have come to light in the past 24 hours.
A 45-year-old man who was hospitalised with symptoms similar to epilepsy and nausea died on Sunday evening, the Press Trust of India news agency reported.
Organochlorines are banned or restricted in many countries after research linked them to cancer and other potential health risks.
It was not immediately clear how extensively the chemicals are used in India, though it is found in DDT applied for mosquito control.
So far, water samples from affected areas have not shown any signs of contamination, and the chief minister’s office said people not linked to the municipal water supply have also fallen ill.
State Chief Minister YS Jagan Mohan Reddy visited a government hospital and met patients.
Opposition leader N Chandrababu Naidu demanded on Twitter an “impartial, full-fledged inquiry into the incident”.
Andhra Pradesh is among the states hit worst by COVID-19, with more than 800,000 detected cases. The health system in the state, like the rest of India, has been frayed by the coronavirus.