Sesen Bio reported that the company has received positive Scientific Advice from the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) related to the regulatory pathway for Vicinium in Europe. The Company’s lead program, Vicinium, also known as VB4-845, is currently in the follow-up stage of a Phase 3 registration trial for the treatment of high-risk, BCG-unresponsive non-muscle invasive bladder cancer (NMIBC). In December 2019, the Company initiated the BLA submission for Vicinium to the United States Food and Drug Administration (FDA) under Rolling Review. Key Elements of CHMP Scientific Advice: The CHMP agreed that the Company’s nonclinical, clinical pharmacology and safety database are all sufficient to support a marketing authorization application (MAA). Furthermore, additional clinical trials were not requested by the CHMP in support of the MAA submission for Vicinium. The CHMP agreed that due to the well-known impact of cystectomy on morbidity and quality of life of patients, a new local treatment that enables patients to avoid radical cystectomy would be meaningful, especially for patients who are contraindicated for cystectomy. The CHMP provided guidance on additional data analyses they expect to be included in the MAA, and the Company is confident that these can be fully addressed with the completed Phase 3 dataset. Based on the guidance received, the Company expects to submit the MAA for Vicinium to the EMA in early 2021, with potential approval anticipated in early 2022. The Company expects to receive Scientific Advice from the CHMP on the Chemistry, Manufacturing and Controls (CMC) program for Vicinium at a later date. Vicinium, a locally administered fusion protein, is Sesen Bio’s lead product candidate being developed for the treatment of high-risk 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. Vicinium is constructed with a stable, genetically engineered peptide tether 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 Sesen Bio, EpCAM has been shown to be overexpressed in NMIBC cells with minimal to no EpCAM expression observed on normal bladder cells. Sesen Bio is currently conducting the Phase 3 VISTA trial, designed to support the registration of Vicinium for the treatment of high-risk NMIBC in patients who have previously received a minimum of two courses of bacillus Calmette-Guérin (BCG) and whose disease is now BCG-unresponsive. Additionally, Sesen Bio believes that cancer cell-killing properties of Vicinium promote an anti-tumor immune response that may potentially combine well with immuno-oncology drugs, such as checkpoint inhibitors. The activity of Vicinium in BCG-unresponsive NMIBC is also being explored at the US National Cancer Institute in combination with AstraZeneca’s immune checkpoint inhibitor durvalumab.