soared in premarket trading Thursday after the company reported the results of a potential ragweed allergy therapy.
A study published in the
New England Journal of Medicine
showed that Dynavax's treatment, given over six weeks to patients with ragweed allergies, effectively reduced allergic responses for 12 months afterward.
Dynavax shares were up $1.29, or 26%, to $6.25.
"The demonstrated therapeutic properties and safety pave the way for a therapeutic intervention that is qualitatively superior to standard immunotherapy," said Dr. Peter Creticos, lead researcher in the trial and a physician at Johns Hopkins.
Results of the study showed a significant reduction in a certain measure of nasal symptoms, with the effects persisting for two ragweed seasons.
Patients given the treatment, dubbed AIC, used no relief medication at all during the second season, while, on average, placebo patients used antihistamines for eight days and decongestants for four days during the two-week peak season.
The treatment was safely tolerated, with no serious side effects reported, Dynavax says. Further studies are continuing.