Successful initial trials of the drug to treat Ebola has led to the authorisation of the drug by Guinea's government for wider use in treatment centres.
The number of people with Ebola in Guinea has doubled in the past week across the three worst affected West African states - Guinea, Liberia and Sierra Leone.
Guinea's anti-Ebola task force said about two dozen new cases of Ebola had been recorded in the last two weeks, taking the total number to 53 as of Friday. Officials are accessing villages where they had previously faced local resistance to their presence.
French and Guinean teams in southern Guinea have tested the experimental Japanese drug Avigan, or favipiravir developed by Toyama Chemical, a subsidiary of Japan's Fujifilm, since mid-December.
French President Francois Hollande's office said that the results had been positive and the drug appeared to accelerate the recovery process of patients.
"We have decided to broaden the use of this drug. It will only be available in the Ebola Treatment Units, not the hospitals," said Sakoba Keita, coordinator of Guinea's Ebola response.
Health officials have not provided any data for the results of the trials of the anti-Ebola drug.
Favipiravir has been distributed to the town of Coyah after testing in Gueckedou and Nzerekore and talks are underway to start the treatment in the capital, Conakry.
"The Ebola situation is getting better but we are not cured," said Jean-François Delfraissy, a French Ebola expert working alongside Guinean authorities to contain the crisis.