What happened

Dynavax Technologies (DVAX -2.19%), a small-cap vaccine and immunotherapy company, is having another volatile day. Shares of the vaccine specialist are down by an eye-popping 17% as of 10:38 a.m. EDT Friday morning.

The biotech's shares are on a wild ride yet again because of news from pharma titan Merck (MRK 2.93%). Merck and its partner Ridgeback Biotherapeutics reported that their oral antiviral pill slashed hospitalization rates in adult COVID-19 patients by half. What's more, the duo noted that no patients on the drug died in the study. Eight people in the placebo component of the trial passed away. 

A businessman looking away from a downward trending graph.

Image source: Getty Images.

So what

Dynavax is collaborating with multiple vaccine developers on responses to the COVID-19 pandemic. Specifically, the biotech has several partnering agreements with various biopharmas regarding its adjuvant CpG 1018, a key component that boosts the effectiveness of a vaccine. Prior to this news, Dynavax was estimating between $300 million and $400 million in 2021 aggregate revenue from its partnership agreements over CpG 1018. This Merck news may not affect the company's near-term revenue estimate. But investors are backing away from nearly all COVID-19 vaccine developers today because of the possible financial ramifications of a drug like Merck's. 

Now what

Should bargain hunters take advantage of Dynavax's double-digit pullback today? I think the answer is yes. It will take Merck and its partner a while to get this drug to market (at least several weeks). And vaccines aren't going to take a monstrous hit from the advent of an oral antiviral. This pill will likely be indicated -- at least initially -- for newly diagnosed patients who have been hospitalized, not the general population. Therefore, biotech investors are probably overreacting to this news today.