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Genotyping Visgen’s HIV Resistance Test Spotlights FDA Reg Concerns


Sometimes it’s not whether you get FDA clearance but whether your competitors need it, as Visible Genetics CEO Richard Daly is learning. His company’s recent SEC filings warn that the FDA’s actions — or lack of — could have a serious impact on its ability to market its HIV resistance genotyping test.

The issue is whether FDA will regulate home-brew tests for HIV resistance. Until last fall, the three major home-brew labs in the US that offered diagnostics to test patients’ resistance to HIV drugs “were really the only game in town,” says Daly. “They had a market share of 85 to 90 percent.” But last fall, Toronto-based Visible Genetics became the first diagnostics company to offer a resistance test that had been approved by the FDA — in a way, trumping the home-brew tests of the other labs.

But the clearance ace isn’t worth much if FDA won’t require the other labs to get approval, too. According to Daly, “there’s an operational understanding that FDA was not going to regulate home-brew tests [in general].” But in the case of HIV testing, “they have issued a guidance document. … It’s not binding,” Daly says, but it comes closer to regulation in this field than FDA has before.

Daly says the FDA’s actions haven’t been much of a roadblock for Visible Genetics’ ability to get a piece of the market so far. “The product’s only been in the field, strongly marketed, for about six weeks, and we’ve already picked up a substantial market share,” he says. (The product was introduced last year in Europe and has also been approved in Canada.) “If that trend continues as it has … we should exit the year with about 55 to 60 percent of the US market.” Daly notes that in most cases where private companies go up against home-brew labs, the labs generally retain about 35 percent of the market.

Visible Genetics made its dent by equipping about 100 labs around the US with the sequencing instruments and diagnostic tests — it provides patients an advantage over the three central labs, which have longer turnaround time because samples have to be shipped to them.

The conflict points to what may become a trend as more and more genomics companies prepare to launch their diagnostic tests — and get FDA clearance, which can cost $30 million, Daly says — in fields where clinical labs already offer unregulated home-brew tests.

“The outcome is really going to depend on where the FDA wants to take it,” Daly says of the HIV resistance testing. “I imagine it will be resolved sometime this year.”

— Meredith Salisbury


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