-- SEA-CD40 with Chemotherapy and an Anti-PD-1 Showed Evidence of Immune Activation, Preliminary Antitumor Activity, and an Acceptable Safety Profile --

Seagen Inc. (Nasdaq:SGEN) today announced data from a phase 1 clinical trial combining SEA-CD40 with chemotherapy and an anti-PD-1 in patients with metastatic PDAC at the ASCO GI annual meeting taking place in San Francisco, January 20 – 22, 2022. SEA-CD40 is a novel, investigational, nonfucosylated monoclonal receptor-agonistic antibody directed to CD40, which is expressed on antigen-presenting cells. In preclinical models, the combination of SEA-CD40 and chemotherapy resulted in antitumor activity which is further enhanced with anti-PD-1 treatment.

In the ongoing phase 1 trial, SEA-CD40 was combined with chemotherapy [gemcitabine and nab-paclitaxel (GnP)], and an anti-PD-1 (pembrolizumab), in 61 patients with untreated metastatic PDAC. Of these, 40 patients received 10 mcg/kg and 21 patients received 30 mcg/kg of SEA-CD40. Key endpoints include confirmed objective response rate (cORR) per RECIST v1.1 by investigator, progression-free survival (PFS) and overall survival (OS).

Activity of SEA-CD40 in combination with GnP and pembrolizumab was observed in both doses of SEA-CD40 tested. The overall (N = 61) cORR was 44 percent, median PFS was 7.4 months (95 percent CI: 5.6-9.0), and median OS was 15.0 months (95 percent CI: 7.8-19.9).

Follow-up for efficacy is ongoing.

The regimen demonstrated a manageable and tolerable safety profile. Overall, ≥ grade 3 treatment-emergent adverse events (TEAEs) were fatigue, nausea, neutropenia, infusion-related reaction, chills, diarrhea, and pyrexia.

This combination also showed evidence of immune activation consistent with the SEA-CD40 mechanism of action.

“Preliminary activity is encouraging based on historical chemotherapy outcomes. Further survival follow up is required to inform our next steps in pancreatic cancer,” said Roger Dansey, M.D., Chief Medical Officer at Seagen. “We are continuing to advance the ongoing phase 2 trial of SEA-CD40 in melanoma and in non-small cell lung cancer.”

The abstract published at the ASCO GI meeting can be found here.

Details of Seagen Presentation at ASCO GI:

More information about the SEA-CD40 phase 1 clinical trial, including enrolling centers, is available by visiting www.clinicaltrials.gov.

About Sugar-Engineered Antibody (SEA) Technology

Seagen's proprietary SEAs are monoclonal antibodies engineered to lack fucose, a sugar molecule that can limit the potential of therapeutic antibodies to engage an anticancer immune response. Enhanced binding to effector cells results in better crosslinking and activation of CD40 signaling in immune cells. Preclinical data indicate SEAs have the potential to work alone and in combination with a broad range of anticancer therapies. The clinical activity and safety of SEAs are currently under investigation.

About Seagen

Seagen is a global biotechnology company that discovers, develops and commercializes transformative cancer medicines to make a meaningful difference in people’s lives. Seagen is headquartered in the Seattle, Washington area, and has locations in California, Canada, Switzerland and the European Union. For more information on the company’s marketed products and robust pipeline, visit www.seagen.com and follow @SeagenGlobal on Twitter.

Forward-Looking Statements

Certain of the statements made in this press release are forward-looking, such as those, among others, relating to the therapeutic potential of SEA-CD40 and sugar-engineered antibodies, their possible safety, efficacy and therapeutic uses, the referenced clinical trials, and anticipated development activities. Actual results or developments may differ materially from those projected or implied in these forward-looking statements. Factors that may cause such a difference include the difficulty and uncertainty of pharmaceutical product development, the risk of adverse events or safety signals, the inability to show sufficient activity in clinical trials and the possibility of adverse regulatory actions. More information about the risks and uncertainties faced by Seagen is contained under the caption “Risk Factors” included in the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2021, filed with the Securities and Exchange Commission. Seagen disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

View source version on businesswire.com: https://www.businesswire.com/news/home/20220118006157/en/