First Results of SAUL - The Largest Safety Study of Its Kind with Atezolizumab in Patients with Metastatic Bladder Cancer

Barcelona, Spain (UroToday.com) First results from SAUL, a Phase IIIb study evaluating the safety of Atezolizumab (Tecentriq®) in approximately 1000 patients with locally advanced or metastatic urothelial carcinoma (mUC) including several clinically relevant populations reflective of real-world clinical practice (patients with renal impairment, poor performance status (ECOG PS 2), treated asymptomatic CNS metastases, stable controlled autoimmune disease)1 was presented during the Breaking News Session by Professor Axel S Merseburger, chairman of the Department of Urology, Campus Lübeck, University Hospital Schleswig-Holstein, Germany.  Data from the study showed that both safety and efficacy, a secondary endpoint, were consistent with previous studies in both the overall population and a subgroup of patients corresponding to the patient population of the pivotal Phase III study, IMvigor211 (“IMvigor211-like”2). The SAUL study is ongoing and further subgroup analyses will also be presented at future medical meetings.

“SAUL is the largest prospective safety study of a cancer immunotherapy in metastatic urothelial carcinoma and provides clinicians with valuable information about Tecentriq in a real-world setting" said Sandra Horning, M.D., Chief Medical Officer and Head of Global Product Development. “We remain committed to improving outcomes for people living with this devastating illness and we look forward to sharing data in the future from our ongoing Phase III studies in early and metastatic disease”.
The data presented at EAU show that the safety of the Tecentriq monotherapy treatment was consistent with the known safety profile of the medicine. Grade 3-4 adverse events (AEs) occurred in 43% of the patients, and treatment-related grade ≥3 AEs occurred in 13% of the patients, with most common reported side effects being fatigue, asthenia, colitis and hypertension (each in 1%). AEs leading to treatment discontinuation happened in 6% of the patients. Additionally, the efficacy results, secondary endpoints of the study, showed overall survival of 10 months (95% CI 8.8–11.9 months) in the IMvigor211-like population. In the overall population, median OS was 8.7 months (95% CI 7.8–9.9). The median duration of follow up was 12.7 months.

The SAUL study is a Phase IIIb, prospective, open label, single arm, multicentre study designed to assess the safety of Tecentriq as a second- to fourth-line treatment for people with locally advanced or metastatic urothelial carcinoma (95%) or non-urothelial carcinoma (5%) of the urinary tract. In addition, the study evaluates the efficacy of Tecentriq and potential tumour biomarkers associated with Tecentriq. It enrolled 1004 people globally, 997 of whom received Tecentriq. IMvigor211-like patients and patients with renal impairment, poor performance status (ECOG PS 2), treated asymptomatic CNS metastases or stable controlled autoimmune disease were eligible. The primary endpoint was safety; secondary endpoints included overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and duration of response (DoR).

References: 
1. Merseburger, A et al. Primary results from SAUL, a prospective multinational single-arm study of atezolizumab (atezo) for locally advanced or metastatic urothelial carcinoma (UC) or non-UC of the urinary tract. 2019
2. Atezolizumab versus chemotherapy in patients with platinum-treated locally advanced or metastatic urothelial carcinoma (IMvigor211): a multicentre, open-label, phase 3 randomised controlled trial. Powles T et al. Lancet. 2018;391:748-757.
3. World Cancer Research Fund. Bladder cancer statistics. Last accessed February 2019
4. World Cancer Research Fund. Comparing more and less developed countries. Last accessed February 2019
5. National Cancer Institute. Bladder Cancer Symptoms, Tests, Prognosis, and Stages (PDQ®)–Patient Version. Last accessed February 2019

EAU 2019 Conference Coverage
Presentation by Axel S. Merseburger, MD: Primary Results from SAUL: A Prospective, Multinational Single-Arm Study of Atezolizumab for Locally Advanced or Metastatic Urothelial Carcinoma of the Urinary Tract