Day One Biopharmaceuticals said Monday more than 90% of patients with brain cancer benefited from its experimental treatment, and the biotech stock skyrocketed.
The company tested its drug, dubbed tovorafenib, in patients age 6 months to 25 years old with an aggressive form of pediatric brain cancer. Overall, the drug achieved a 91% clinical benefit rate — meaning more than nine in 10 patients completely or partially responded, or were considered stable for six months.
Further, tumors shrank in 64% of patients. All patients deemed to have stable disease experienced tumor shrinkage. Their tumors diminished 19%-43% in size, Day One said in a news release.
"These initial findings underscore the potential of tovorafenib monotherapy to become a significant and transformative new option for relapsed/progressive pediatric low-grade glioma," Day One Chief Medical Officer Samuel Blackman said in a written statement.
On the stock market today, the biotech stock rocketed 126% to 14.96.
Biotech Stock Targets Pretreated Patients
The initial data is based on the first 22 patients who could be evaluated.
At the median, patients began responding at 2.8 months after beginning treatment. It's important to note, Day One tested tovorafenib in patients for whom a median of three previous treatments didn't work. All responding patients remain on treatment.
Promisingly for the biotech stock, no patients have discontinued treatment due to a side effect related to the drug. The most common side effects were increases in an enzyme called creatine in the blood, rash and hair color changes. But more than a third of patients, 36%, experienced serious side effects.
Based on the results, Day One now plans to begin a pivotal study in previously untreated patients with the same form of cancer. It also expects to complete the current study in the first quarter of 2023.
The news sent the biotech stock rocketing to its highest point since January. Day One is relatively new to the public markets, debuting on Nasdaq in mid-2021. Shares have traded down since, however. On Monday, the biotech stock easily surged above its 50-day moving average in high volume, according to MarketSmith.com.
Follow Allison Gatlin on Twitter at @IBD_AGatlin.