January 13, 2020 - The case was voluntarily dismissed.

May 21, 2020 - An investor in shares of CytomX Therapeutics, Inc. (NASDAQ: CTMX) filed a lawsuit in the U.S. District Court for the Northern District of California over alleged violations of Federal Securities Laws by CytomX Therapeutics, Inc. in connection with certain allegedly false and misleading statements made between May 17, 2018, and May 13, 2020.

San Francisco, CA based CytomX Therapeutics, Inc. operates as an oncology-focused biopharmaceutical company in the United States. The Company develops a novel class of investigational antibody therapeutics based on its Probody technology platform for the treatment of cancer. CytomX’s lead product candidates in the clinical stage include, among others, CX-072 and CX-2009. CytomX Therapeutics, Inc has been evaluating CX-072 in its “PROCLAIM” series clinical program for several years.

For example, the PROCLAIM-CX-072-001 clinical trial was designed to assess the tolerability and preliminary antitumor activity of multiple doses of CX-072 as a monotherapy or as a combination therapy with ipilimumab (which Bristol-Myers Squibb Company markets under the brand name Yervoy) or vemurafenib (which Roche markets under the brand name Zelboraf) in patients with advanced, unresectable solid tumors or lymphoma. CytomX Therapeutics, Inc also began conducting a Phase 2 clinical trial called PROCLAIM-CX-072-002, which was initiated in October 2019 and is an open-label, multi-center clinical trial evaluating CX-072 in combination with ipilimumab in patients with unresectable or metastatic melanoma.

Likewise, CystomX had been evaluating CX-2009 under its own “PROCLAIM” brand clinical program. This program includes the PROCLAIM-CX-2009-001 clinical trial, which is a Phase 1/2 trial evaluating the tolerability and preliminary antitumor activity of CX-2009 as a monotherapy, which CytomX initiated in June 2017. This clinical program also proceeded in multiple parts—Parts A and A2, which are monotherapy dose escalation studies; and Part B, which is a Phase 2 expansion study of CX-2009 monotherapy at 7 mg/kg administered every three weeks in up to 40 patients with hormone receptor (ER, PR) positive, HER2 negative breast cancer, which Defendants announced in December 2019 based on the tolerability and activity data from Part A and A2 of the study.

On May 13, 2020, CytomX Therapeutics, Inc made available abstracts for the Company’s clinical presentations for CX-072 and CX-2009. Results from the PROCLAIM-CX-072 clinical program showed a response rate of 8.8%, compared to a response rate of 18.5% in patients receiving the combination of CX-072 and ipilimumab.

Meanwhile, results from the PROCLAIM-CX-2009 clinical program showed “evidence” of clinical activity at doses at least 4 mg/kg 3x/week, but also suggested a significantly higher rate of serious or greater treatment-related toxicity to the eyes at dose equivalents at least 8 mg/kg 3x/week.

Shares of CytomX Therapeutics, Inc. (NASDAQ: CTMX) declined from $15.32 per share on May 12, 2020, to as low as $8.61 per share on May 15, 2020.

According to the complaint the plaintiff alleges on behalf of purchasers of CytomX Therapeutics, Inc. (NASDAQ: CTMX) common shares between May 17, 2018, and May 13, 2020, that the defendants violated Federal Securities Laws.

More specifically, the plaintiff claims that between May 17, 2018, and May 13, 2020, the defendants failed to disclose to investors that CytomX had downplayed issues with CX-072’s efficacy observed in the PROCLAIM-CX-072 clinical program, that CytomX had similarly downplayed issues with CX-2009’s efficacy and safety observed in the PROCLAIM-CX-2009 clinical program, and that as a result, the Company’s public statements were materially false and misleading at all relevant times.