Phase 3 Registration Trial for Non-Muscle Invasive Bladder Cancer Achieves 42% Complete Response Rate at Three Months in Carcinoma in Situ Patients
Data Presented During Plenary Session at
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“High-grade NMIBC is a devastating cancer that typically occurs later in life and for which treatment options are limited. Over the last 30 years, our industry has seen little innovation for the treatment of this prevalent cancer. The current standard-of-care, BCG, works in many patients, but many will also eventually relapse. For those patients who relapse or who don’t respond at all, the standard alternative is radical cystectomy. In a cystectomy, the bladder is removed along with surrounding lymph nodes and other organs that contain cancer. I am very encouraged by both the safety and these three-month efficacy data with Vicinium, and I look forward to continuing to work with the
“The VISTA Trial three-month data are encouraging for our company and the patients with high-grade NMIBC who have been underserved for many years,” said Stephen Hurly, president and chief executive officer of
VISTA Trial Design and Patient Cohorts
The Phase 3 VISTA Trial completed recruitment in
The clinical trial includes three patient cohorts based on histology and time to recurrence after adequate BCG:
- Cohort 1 (n=87): patients with CIS with or without papillary disease whose cancer recurred within six months of their last course of BCG treatment.
- Cohort 2 (n=6): patients with CIS with or without papillary disease whose cancer recurred after six months, but before 11 months, after their last course of BCG treatment.
- Cohort 3 (n=40): patients with papillary disease without CIS whose cancer recurred within six months of their last course of BCG treatment.
Three-Month Efficacy Results: CIS Patients
In cohort 1, 72 patients were evaluable for three-month data as of the
Three-Month Efficacy Results: Papillary Patients
Patients with papillary disease without CIS were enrolled in cohort 3, but are not included in the primary endpoint assessment. At screening, all of these patients underwent mandatory resection of their tumors and upon starting treatment, were deemed to have no visible evidence of disease. As such, in this patient population, rates of disease recurrence and time to disease recurrence are standard criteria to evaluate response. In these evaluable patients (n=34), treatment with Vicinium demonstrated a 68 percent recurrence-free rate at three months.
Preliminary Safety Results
To date, Vicinium has been well-tolerated in the VISTA Trial. In treated patients across cohorts (n=129), 72 percent of all adverse events were Grade 1 or 2. The most commonly reported treatment-emergent adverse events (all grades) were urinary tract infection (29%), dysuria (19%), hematuria (16%), pollakiuria (12%), diarrhea (10%), fatigue (10%), micronutrition urgency (9%), nausea (8%) and increased lipase (8%, all asymptomatic). Of the treatment-related adverse events, four percent were Grade 3 or 4, with no Grade 5 treatment-related adverse events. Four treatment-related serious adverse events were reported, including acute kidney injury or renal failure and cholestatic hepatitis.
“The positive, three-month data from the VISTA Trial support Vicinium’s potential to offer a new and completely different treatment option for patients who need it,” said
Conference Call Information
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About the VISTA Clinical Trial
The VISTA Trial is an open-label, multicenter, single-arm Phase 3 clinical trial evaluating the efficacy and tolerability of Vicinium™ in patients with high-grade non-muscle invasive bladder cancer (NMIBC) that is carcinoma in situ (CIS), which is cancer found on the inner lining of the bladder that has not spread into muscle or other tissue) and/or papillary, which is cancer that has grown from the bladder lining out into the bladder but has not spread into muscle or other tissue, who have been previously treated with bacillus Calmette-Guérin (BCG). The primary endpoint of the trial is the complete response rate in patients with CIS with or without papillary disease. Patients in the trial receive locally administered Vicinium twice a week for six weeks, followed by once-weekly treatment for another six weeks, then treatment every other week for up to two years. Twelve-month data are anticipated in mid-2019. To learn more about the Phase 3 VISTA Trial, please visit www.clinicaltrials.gov and search the identifier NCT02449239.
Vicinium™, also known as VB4-845, is Sesen Bio’s lead product candidate and is a next-generation antibody-drug conjugate (ADC), developed using the company’s proprietary Targeted Protein Therapeutics platform, for the treatment of high-grade non-muscle invasive bladder cancer (NMIBC). Vicinium is comprised of a recombinant fusion protein that targets epithelial cell adhesion molecule (EpCAM) antigens on the surface of tumor cells to deliver a potent protein payload, Pseudomonas Exotoxin A (ETA). Vicinium is constructed with a stable, genetically engineered peptide linker to ensure the payload remains attached until it is internalized by the cancer cell, which is believed to decrease the risk of toxicity to healthy tissues, thereby improving its safety. In prior clinical trials conducted by
About Non-Muscle Invasive Bladder Cancer
Bladder cancer is the sixth most commonly diagnosed cancer in
Cautionary Note on Forward-Looking Statements
Any statements in this press release about future expectations, plans and prospects for the Company, the Company’s strategy, future operations, and other statements containing the words “anticipate,” “believe,” “estimate,” “expect,” “intend,” “may,” “plan,” “predict,” “project,” “target,” “potential,” “will,” “would,” “could,” “should,” “continue,” and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: the uncertainties inherent in the initiation and conduct of clinical trials, the possibility that the three-month data of the Phase 3 VISTA Trial are not indicative of final clinical results and final clinical trial results may not be positive with regard to the safety or efficacy of Vicinium, our ability to successfully develop our product candidates and complete our planned clinical programs, our ability to obtain marketing approvals for our product candidates, expectations regarding our ongoing clinical trials, availability and timing of data from clinical trials, whether interim results from a clinical trial will be predictive of the final results of the trial or results of early clinical studies will be indicative of the results of future studies, the adequacy of any clinical models, expectations regarding regulatory approvals and other factors discussed in the “Risk Factors” section of the Company’s Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and other reports filed with the Securities and Exchange Commission. In addition, the forward-looking statements included in this press release represent the Company’s views as of the date hereof. The Company anticipates that subsequent events and developments will cause the Company’s views to change. However, while the Company may elect to update these forward-looking statements at some point in the future, the Company specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing the Company’s views as of any date subsequent to the date hereof.