ZURICH (REUTERS) - Drugs being re-purposed in hopes they will help against Covid-19 cost little to make but may prove challenging to produce in quantities needed for a pandemic, a drug pricing expert said.
"Any pharmaceutical company manufacturing any treatment currently in clinical trials against coronavirus needs a clear plan to upscale production massively," Mr Andrew Hill, a University of Liverpool research fellow, told Reuters.
"Otherwise, supplies of these drugs could quickly run out."
In a study released on Friday (April 10) in the Journal of Virus Eradication, Mr Hill and five other researchers, including Howard University chemist Joseph Fortunak, examined the cost of manufacturing medicines in recent or ongoing Covid-19 trials.
Using prices for active pharmaceutical ingredients to build estimates, they said Gilead Science's experimental drug remdesivir, originally for Ebola, could be made for as little as US$0.93 (S$1.30) for a day's supply.
Gilead said the figure does not "accurately reflect" manufacturing costs at scale, but did not give those costs.
Fujifilm Holdings Corp's flu drug Avigan runs US$1.45 to make per day, the researchers said. Fujifilm did not immediately comment.
Meanwhile, decades-old malaria medicine hydroxychloroquine - touted by US President Donald Trump and others as a possible game changer despite no scientific proof that it works - costs eight US cents.
Other drugs the researchers examined included the related malaria medicine, chloroquine, the antibiotic azithromycin, Roche's lung drug Esbriet and arthritis treatment Avastin, as well as an AbbVie HIV drug and a Hepatitis C cocktail.
"Should repurposed drugs demonstrate efficacy against Covid-19, they could be manufactured profitably at very low costs," the authors wrote, giving range of between US$1 and US$29 per course of treatment.
Nonetheless, demand for medicines that prove their mettle could swiftly outstrip supply, necessitating new industry alliances, parallel manufacturing by multiple companies, and shared intellectual property, Mr Hill said.
"The demands could be huge, and could lead to shortages for people normally taking these drugs for other diseases," he added.
Roche, which received US$25 million in US funding for Actemra's Covid-19 trial, did not respond to questions about boosting production.
For Fujifilm's Avigan, Japan provided some US$128 million to boost supplies to treat two million people, as triple the dose is required for Covid-19 than for influenza.
Gilead can produce 140,000 remdesivir treatment courses near-term, and one million-plus by December, it has projected.
Sanofi can make millions of hydroxychloroquine doses, but whether that suffices may depend on if trials show it should be used for potentially millions of mildly affected patients, or for only severe ICU patients, chief executive Paul Hudson told Reuters last week.
Sanofi has boosted production of hydroxychloroquine by 50 per cent across its eight manufacturing sites worldwide and said on Friday it would donate 100 million doses to 50 countries, while Novartis has pledged 130 million doses and said it is hunting for more ingredients, should trials show the medicine works.
So far, some doctors including in China say results have been inconclusive.