Culver City-based NantKwest Inc. and El Segundo-based ImmunityBio have announced plans to combine in a stock-for-stock transaction. 

The reverse merger will retain NantKwest’s public listing on the NASDAQ exchange, but will be named ImmunityBio. The combined entities’ ticker is expected to change to IBRX, according to the companies.

As part of the transaction, ImmunityBio stockholders will receive 0.8190 shares of NantKwest for each share of ImmunityBio owned. Current ImmunityBio shareholders will own about 72% of the combined company with NantKwest shareholders controlling the remaining 28%.

NantKwest and ImmunityBio are both part of local billionaire Patrick Soon-Shiong’s NantWorks conglomerate. The biotech mogul was, until recently, the chief executive of NantKwest. In late October, he passed that role to Richard Adcock, a longtime health care executive.

Adcock will serve as CEO of the combined organization following the merger.

“We are excited to join forces with ImmunityBio, a company and team we have collaborated with for many years across our platforms,” Adcock said in a statement. “With the integration of ImmunityBio’s pipeline, cutting-edge R&D capabilities, talented employees and clinical expertise, we expect to accelerate the delivery of new treatments for patients with unmet needs. Together we can unlock the combined potential of our assets, and look forward to building on our continued success as one company.”

NantKwest and ImmunityBio have a long history of working together, including on a Covid-19 vaccine candidate. The combined companies say they will have a significant pipeline of clinical-stage cancer treatments treatments, including 13 currently in clinical trials —  11 of which are in phase II to III trials.

“What distinguishes the merged entity is the late stage immunotherapy product pipeline that is designed to eliminate the need for high-dose chemotherapy, improve the outcomes of current CAR T cell therapies, and extend beyond checkpoint inhibitors,” Soon-Shiong said in a statement. “With 13 clinical trials across multiple tumor types at Phase I to III and with the combined talent in research, clinical development and manufacturing, the merged entity is poised to be a leader in the immunotherapy space.”

In a separate announcement concurrent with the merger news, ImmunityBio reported a 71% positive response rate in a recent study for its bladder treatment drug.

NantKwest’s stock was up more than 56% at market close the day of the announcements.