New Therapy Shows Promise in Fighting Bladder Cancer

Introduction

Exciting new research presented at the 2024 ASCO Annual Meeting has revealed promising results for patients with high-risk non-muscle-invasive bladder cancer (NMIBC) who do not respond to the standard Bacillus Calmette-Guerin (BCG) treatment. The study explored the effectiveness of the combination of two drugs: cretostimogene grenadenorepvec and pembrolizumab (Keytruda).

The CORE-001 Trial

The CORE-001 trial, a phase 2 study, investigated how well these two drugs worked together to treat NMIBC. This bladder cancer does not penetrate deep muscle layers but can still be serious and requires aggressive treatment. In the study, 35 patients who had not responded to previous BCG treatment were given a combination of cretostimogene grenadenorepvec and pembrolizumab.

Impressive Results

After 12 months, more than half the patients (57%) showed a complete response, meaning no signs of cancer were detected. Even more impressive, 83% of patients experienced cancer remission at some point during the study. After 24 months, over half of these patients maintained their response to treatment.

Long-Term Benefits

The findings are particularly significant because none of the patients saw their cancer progress to a more severe stage. The progression-free survival rate was 100%, indicating that the cancer did not get worse in any of the patients during the study period.

Safety and Side Effects

The combination treatment was well-tolerated, with side effects similar to those seen in studies using either of the drugs alone. Most side effects were mild and temporary.

Efficacy Comparisons

During the ASCO presentation, Dr. Roger Li from Moffitt Cancer Center noted that this combination therapy compared favorably to other treatments tested in similar studies. For instance, treatments like nadofaragene firadenovec or N-803 plus BCG showed slightly lower success rates.

How the Treatment Works

This treatment involved an initial phase with six weekly intravesical instillations (bladder injections) of cretostimogene. Patients who still had cancer after 12 weeks received another set of six weekly treatments. Those who responded well continued to receive maintenance treatments every 3 months. Pembrolizumab was given intravenously every six weeks for up to 24 months.

Looking Ahead

The success of the CORE-001 trial has led to further investigations. Future trials will test whether cretostimogene alone or in other combinations can serve as an effective treatment.

Regulatory Approvals

The FDA has recognized the potential of cretostimogene by granting it Breakthrough Therapy and Fast Track Designations. These designations mean that the further development and review of this drug will be expedited.

Broader Implications

If these findings hold up in larger studies, this combination therapy could offer a new, less invasive treatment option for patients with high-risk NMIBC, potentially sparing them from the need for more drastic measures like bladder removal.