ASCO 2026: SAKK 06/19 Shows Promising Results in Bladder Cancer
The Swiss Cancer Institute is pleased to share the results of the phase II SAKK 06/19 trial, presented by Prof. Dr. Richard Cathomas at the 2026 Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago.
Muscle-invasive bladder cancer is an aggressive disease that often requires a combination of systemic treatment and surgery. While recent advances in chemoimmunotherapy have improved outcomes, there remains a need for more effective treatment strategies that can further reduce the risk of residual disease before surgery.
The SAKK 06/19 study investigated a novel approach by combining intravesical recombinant Bacillus Calmette-Guérin (rBCG) with perioperative chemoimmunotherapy. BCG has been used successfully for decades in non-muscle-invasive bladder cancer. However, this is the first prospective clinical trial to evaluate a recombinant form of BCG in combination with chemoimmunotherapy for muscle-invasive disease.
A total of 47 patients with operable muscle-invasive bladder cancer were enrolled across Switzerland. Patients received intravesical rBCG followed by immunotherapy and chemotherapy before undergoing surgery.
The study achieved a pathological complete response rate of 68%, meaning that no residual cancer was detected in the surgical specimen in more than two-thirds of operated patients. In addition, the pathological overall response rate reached 83%.
Importantly, the treatment combination demonstrated a favourable safety profile and was feasible to administer in this patient population. No unexpected safety concerns related to rBCG were observed.
These encouraging findings suggest that adding rBCG to modern chemoimmunotherapy may further enhance anti-tumour activity in muscle-invasive bladder cancer. The results provide a strong rationale for future randomized trials to confirm the potential benefit of this treatment strategy.
The Swiss Cancer Institute thanks all participating patients, investigators and study teams whose commitment made this research possible.
The full publication can be accessed here: