Dive Brief:

• An experimental drug from CG Oncology has driven bladder cancers into remission in about three-quarters of people who received it in a Phase 3 trial, matching results the biotechnology company disclosed from a smaller number of study participants last year.
• CG previously said 50 of 66 trial volunteers with non-muscle invasive bladder cancer had no detectable disease after receiving its drug, known as cretostimogene. On Friday, the company presented new data showing 79 of 105 had had complete responses. Additionally, CG said 29 of 35 participants followed for at least 12 months are still cancer-free, though another 22 still await further scans.
• Among the most common side effects associated with cretostimogene were bladder spasms, frequent urination and blood in urine. Two patients had adverse events judged by study investigators as serious — clotting or inflammation in the bladder — but no participants discontinued treatment. CG will reveal final study results later this year, and could seek regulatory approval afterwards.

Dive Insight:

Non-muscle invasive bladder cancer — where cancer cells are only on the bladder’s inner lining, and haven’t yet spread further — is typically treated with a type of immunotherapy called BCG following a tumor resection.

But those interventions don’t work for everyone, and according to CG, about half of those who respond see their cancers return, after which there are limited and more drastic options such as chemotherapy and surgical removal of the bladder.

CG is one of several companies trying to expand on those options. Its drug, cretostimogene, is a type of immunotherapy known as an oncolytic virus. CG is testing the drug in different settings, touting its potential as the possible “backbone” of future drug combinations. An ongoing Phase 2 trial is evaluating cretostimogene alongside Merck & Co.’s immunotherapy Keytruda. Results are expected at the American Society of Clinical Oncology meeting later this month.

But CG faces competition. Since 2020, the Food and Drug Administration has approved Keytruda, a gene therapy from Ferring Pharmaceuticals and an immunotherapy developed by ImmunityBio. A Johnson & Johnson medical device that releases chemotherapy into the bladder is also in testing and has shown promising results. Additional results were to be presented at a medical meeting Friday as well.

Still, Wall Street analysts and investors have been supportive of CG’s chances. The company in January raised $380 million in the sector’s largest initial public offering this year. In a February report, Cantor Fitzgerald analyst Josh Schimmer called the offering “one of the highest-demand investment opportunities I’ve seen,” citing the company’s study results, development plans and cretostimogene’s potentially long-lasting market exclusivity.

Cretostimogene profile “is very competitive, and the market is large enough to accommodate multiple entrants,” Schimmer wrote. He estimates the drug, if approved, can bring in more than $1 billion in peak yearly sales.

The study results reported on Friday build on those findings and provide a more comprehensive look at how CG’s drug stacks up. The trial, BOND-003, is evaluating the drug as a monotherapy in people who haven’t responded to BCG therapy and are at “high risk” of a recurrence.

CG has now evaluated 105 of its 112 participants for efficacy, which CEO Arthur Kwan, in an interview, called “the largest dataset that we’re aware of ever reported in this space.”

The drug’s complete response rate at any time after therapy, its main study goal, has held at about 75% even with more patients enrolled. Kwan also pointed out that just over 92% of those who received CG’s drug didn’t need their bladders removed. Neither did any participant with a complete response. The company intends to track bladder removals going forward.

“Most patients will tell you that they’d rather avoid that and try something else, which is exactly why the FDA has taken such a keen interest in this population,” he said.

Kwan acknowledged the competition CG faces, as well as the fact that the numbers could shift as more scans are done on the study’s remaining patients.

But while comparing drugs across trials is difficult, he noted that the complete response rates for cretostimogene appear higher than what’s been observed in testing of Merck, Ferring and ImmunityBio’s therapies. CG is also now moving earlier in a person’s disease course, testing its therapy in patients with “intermediate risk” of recurrence.

“It’s just the beginning,” he said.