The Boston firm announced Tuesday that studies of three experimental drug combinations all reported notable improvement in patients who have a different underlying genetic pattern than patients already eligible for current commercial products. If all plays out well, up to 90 percent of people with CF could have a drug to treat their disease in a few years.
As of 11 p.m. ET, investors have boosted Vertex shares nearly 34 dollars, or 25.6 percent, to $166.00 in after-hours trading.
Each triple is based on a backbone of two drugs, both owned by Vertex: the approved ivacaftor (Kalydeco) and the experimental tezacaftor. Nearly four months ago, Vertex reported Phase 3 data for the ivacaftor-tezacaftor duo that, if approved, would give Vertex products to treat up to 40 percent of the global cystic fibrosis (CF) population.
With today’s data release, Vertex is making a case to treat up to 90 percent of all CF patients, including those with a “minimal function” mutation that causes a severe form of the disease.
CF is a genetic disease that causes a steady buildup of thick mucus in the lungs and pancreas. It stems from an array of mutations to the gene that produces a protein called CFTR, which in healthy people helps cells pump salt and water in and out. Without enough CFTR, organs develop a buildup of mucus and other problems, such as bacterial infections, respiratory failure, and difficulty breaking down food. The disease affects about 30,000 patients in the U.S. and 75,000 worldwide. CF patients live to a median of 40 years old, according to the Cystic Fibrosis Foundation.
All studies reported Tuesday tested one group with a minimal function mutation in one of their CFTR genes and a 508del mutation in the other. The studies also tested patients with two 508del mutations—the same group eligible for Vertex’s commercial products.
Each triple combination uses a different experimental Vertex drug (VX-440, VX-152, VX-659) on top of ivacaftor-tezacaftor. Vertex officials said today they would choose at least one to start pivotal studies next year, with hopes of garnering FDA approval if all goes well.
A quick rundown of the three studies under discussion Tuesday:
—VX-440, ivacaftor, tezacaftor: A Phase 2 study with 47 patients in one arm and 26 patients in another. Both arms tested efficacy over four weeks. Patients with a minimal function mutation fared 10 to 12 percent better in lung function after four weeks, depending on the VX-440 dose level.
—VX-152, ivacaftor, tezacaftor: A Phase 2 study with 21 patients in one arm and 14 patients in another. Patients with a minimal function mutation fared 5.6 to 9.7 percent better in lung function after two weeks, depending on the VX-152 dose level.
—VX-659, ivacaftor, tezacaftor: A Phase 1 safety study that tested VX-659 alone and in triple combination with healthy volunteers; it also tested the triple combination in 9 CF patients with a minimal function mutation; three others took placebo. The CF patients fared 9.6 percent better after two weeks.
In the first two studies, patients in the smaller arms had two copies of the 508del mutations. They also showed lung improvement of 10 percent and 7.5 percent, respectively.
Vertex said that side effects were mild to moderate across all three studies.