First Mainland China Patient Dosed in Pivotal Phase 2 Trial Testing MOR202 in Multiple Myeloma

I-Mab Biopharma has dosed the first patient in mainland China in its ongoing, pivotal Phase 2 trial assessing MorphoSys‘s investigational antibody therapy MOR202 (TJ202) as treatment for people with relapsed or refractory multiple myeloma, the company announced.

The announcement comes less than three months after Chinese regulatory authorities issued an Investigational New Drug clearance for MOR202. That decision, by the National Medical Products Administration (NMPA), allowed clinical trials ongoing in Taiwan to expand to sites in mainland China.

“We are pleased that the first patient has been successfully dosed in mainland China,” Jingwu Zang, MD, PhD, founder and honorary chairman of I-Mab Biopharma, said in a press release.

“The initiation of enrollment in China of TJ202/MOR202 is an important milestone. We look forward to accelerating TJ202/MOR202 clinical program significantly towards registration, which will benefit the patients with multiple myeloma in China,” Zang added.

MOR202 is an experimental antibody developed by MorphoSys that binds to the CD38 surface molecule, found in virtually all multiple myeloma cells. Once bound to its target, the antibody delivers signals that instruct the immune system to kill the malignant cells.

The treatment candidate, licensed to I-Mab for development and commercialization in the greater China region, is being tested in previously treated multiple myeloma patients in two registrational clinical trials. Registrational trials are large confirmatory studies meant to establish an acceptable benefit/safety profile in order to gain regulatory approval for a new therapy. Initiated in Taiwan in early 2019, the studies were later expanded to mainland China, in October of last year.

The Phase 2 trial (NCT03860038), in which the first mainland China patient was recently dosed, is assessing MOR202 plus the corticosteroid dexamethasone in people who received at least two prior lines of therapy, including a proteasome inhibitor and an immunomodulator.

Participants ages 18 and older are still being recruited, to a target enrollment of 82 patients. The trial’s primary goal is to determine the proportion of patients who respond partially or completely to the therapy. Secondary goals include those who achieve at least stable disease, duration of response, time to disease worsening or death, and overall survival.

The researchers also will examine minimal residual disease — the presence of very small amounts of cancer cells in the bone marrow following treatment, which might lead to relapse — status as an exploratory measure. Top-line data are expected by late 2021.

The second pivotal study is an open-label, randomized Phase 3 trial (NCT03952091) to assess the effectiveness of adding MOR202 to standard Revlimid (lenalidomide) and dexamethasone treatment. The researchers are examining whether MOR202 extends the time participants — myeloma patients who received at least one prior line of treatment — live without disease worsening.

In a prior Phase 1/2 trial (NCT01421186), this combination yielded very good outcomes in relapsed or refractory multiple myeloma patients, with 65% of participants responding to treatment. The results showed 12% complete responses and 18% very good partial responses. Participants in this trial receiving MOR202 and dexamethasone had a 28% response rate.

The Phase 3 trial, also still recruiting, is expected to include approximately 291 patients, who will be randomly assigned to receive a triple combination of MOR202, Revlimid, and dexamethasone, or Revlimid plus dexamethasone only. Top-line data from this trial is expected by July 2022.

If successful, the two trials may lead to the approval of MOR202 in greater China for the two indications tested.