What happened

Opko Health (NASDAQ:OPK) -- considered a coronavirus stock thanks to its BioReference Laboratories, which has diagnostics products that test for the globe's top health threat at the moment -- closed nearly 13% lower on Friday. 

The apparent cause was the company's Q2 fiscal 2020 results, which clearly disappointed investors even though the healthcare company notched beats on both the top and bottom lines.

Medical professional writing on a document held with a clipboard.

Image source: Getty Images.

So what

Opko's revenue rose a sturdy 33% on a year-over-year basis to just over $301 million, thanks in no small part to the dramatic expansion of BioReference's business during the coronavirus pandemic.

On the bottom line, the company flipped to a net profit of $33.7 million ($0.05 per share), from the year-ago loss of almost $60 million.

Both headline numbers thrashed analyst projections. On average, prognosticators following the stock were modeling around $216 million in revenue, and a per-share net loss of $0.07.

Now what

A sell-off is typically the opposite of what happens when a company delivers an estimate-trouncing quarter. With Opko, investors might be concerned that sales of the company's products (as opposed to services) were relatively weak, even though this revenue stream is much thinner. 

They might also be worried that the company did not proffer guidance, although this is not unusual for companies in any sector during these very uncertain times.

Whatever the reason or reasons, the very negative reaction seems unwarranted. It won't be surprising to see Opko stock rise again, particularly on good news.