BeiGene Ltd.'s Brukinsa medicine failed to show it worked better than Johnson & Johnson and AbbVie Inc.'s Imbruvica in a late-stage study of certain patients with a rare type of blood cancer, missing the study's main goal.
The Chinese biotechnology company's stock was down about 2.5% to $171.65 as of 10:23 a.m. in Nasdaq trading Dec. 16. The shares had fallen as low as $162.50.
BeiGene evaluated Brukinsa, or zanubrutinib, against Imbruvica, or ibrutinib, in a phase 3 trial, dubbed Aspen. The trial included patients with Waldenström's macroglobulinemia whose cancer returned or did not respond to prior therapy, as well as patients who had not received any prior therapy for the disease.
Waldenström's macroglobulinemia is a rare type of non-Hodgkin lymphoma that begins in the white blood cells. The condition is characterized by the presence of too many B lymphocytes, a kind of white blood cell. The cells accumulate, resulting in an oversupply of an antibody protein known as immunoglobulin. The blood then thickens, which can lead to ruptures in smaller blood vessels.
The study enrolled 229 patients, divided into two groups. The first group consisted of 201 patients, who received either Brukinsa or Imbruvica. The second group consisted of 28 people who received Brukinsa because these particular patients had previously responded poorly to Imbruvica. Results from the second group had been previously presented at a scientific conference.
BeiGene said Brukinsa did not show statistical significance in achieving a complete response in patients when compared to patients on Imbruvica, which is approved in the U.S., in combination with Roche Holding AG's Rituxan, to treat adult patients with Waldenström's macroglobulinemia.
Complete response refers to the disappearance of all signs of cancer in response to treatment.
The company noted its Dec. 16 press release that data from group 1 showed that a very good partial response to treatment was seen in 28.9% of patients whose cancer returned or did not respond to therapy prior to receiving Brukinsa, compared to 19.8% of similar patients on Imbruvica. However, the difference was not statistically significant.
BeiGene also said no patients showed a complete response in either arm of the study.
The company said that out of all the patients receiving Brukinsa there was one fatal adverse event, or death, while four patients discontinued treatment due to adverse events. For patients on Imbruvica, there were four deaths, while nine patients stopped taking the medicine due to adverse events. The rate of neutropenia, a condition that can increase the risk of infection, was greater in the Brukinsa group than in the Imbruvica group.
In November, Brukinsa was approved in the U.S. to treat certain adult patients with a rare kind of non-Hodgkin lymphoma called mantle cell lymphoma.