What are Antibody Therapies?

Antibody therapies augment the naturally occurring antibodies in our immune system that help the immune system recognize infections.3 Antibodies have been developed to help identify and attack malignant cells in multiple myeloma, and in other cancers. Multiple novel combinations of antibody therapeutics are now available for the management of multiple myeloma. These include1,4-6:

  • Signaling lymphocyte activation molecular family 7 (SLAMF7) antibodies
  • Anti-CD38 antibodies
  • B-cell maturation antigen (BCMA)-targeted antibody-drug conjugates

In addition to these therapies, multiple other therapies are now in development called bispecific antibodies. These antibodies can help bring together T cells, which are immune cells involved in targeting and destroying cancer cells, and specific receptors on cancer cells. In this way, bispecific antibodies can help the immune system recognize and destroy cancer. One target on cancer cells in multiple myeloma is known as B-cell maturation antigen (BCMA). With approval secured for one bispecific antibody, teclistamab, additional bispecific antibodies targeting BCMA are in active development for multiple myeloma, including7,8:

  • Linvoseltamab (REGN5458)
  • Alnuctamab (CC-93269)
  • Elranatamab (PF-06863135)

If you have already received multiple earlier lines of therapy, discussing these therapies with your physician might give rise to consideration of clinical trial opportunities in developing lines of therapy.8

Note: This CME program was recorded prior to the American Society of Clinical Oncology (ASCO) 2023 meeting in June 2023. Highlights of data released at ASCO include:

Teclistamab

Longer-term data of the Phase 1/2 MajesTEC-1 study showed a high rate of deep and durable response in triple-class exposed MM patients. At 22 median follow up; complete response or better = 43%; duration of response = 24 months (27 months for ≥CR); median PFS = 12.5 months (20 months for ≥CR); median OS = 21.9 months (not reached for ≥CR).

Adverse event profile for all patients (and grade 3/4) included: infections = 78% (52%); CRS = 72% (0.6%); neutropenia = 72% (65%); anemia = 54% (38%); thrombocytopenia = 42% (22%); and lymphopenia = 35% (33%). ICANS occurred in 3% of patients, all grade 1 or 2.

Reference: van de Donk NWCJ, et al. Long-term follow-up from MajesTEC-1 of teclistamab, a B-cell maturation antigen (BCMA) x CD3 bispecific antibody, in patients with relapsed/refractory multiple myeloma (RRMM). J Clin Oncol. 2023;41(suppl 16):8011. doi:10.1200/JCO.2023.41.16_suppl.8011

Linvoseltamab (investigational)

Two Phase 2 full dose cohorts (50 mg and 200 mg) in the LINKER-MM1 trial were studied to optimize dose selection. Linvoseltamab 200 mg showed better efficacy compared with 50 mg, including in patients with high disease burden. The 200 mg dose had consistent efficacy across high-risk subgroups and induced responses in pts who progressed on 50 mg. The recommended dose for further study is now 200mg.

ORR for 200 mg dose = 71%; CR = 30%; very good partial response = 59%. Median duration of response = not reached. The probability of maintaining response at 6 months was 84% and 79% at 12 months. Treatment-emergent adverse events were reported in 95% of patients (grade 3 or higher = 79%): CRS = 45% (1%); neutropenia = 33%; fatigue = 33%; anemia = 27% (24%). ICANS ≥grade 3 = 2%.

References:

Lee HC, et al. LINKER-MM1 study: Linvoseltamab (REGN5458) in patients with relapsed/refractory multiple myeloma. J Clin Oncol. 2023;41(suppl 16):8006. doi:10.1200/JCO.2023.41.16_suppl.8006

Updated Linvoseltamab (BCMAxCD3) Data from pivotal trial demonstrates early, deep, and durable responses in patients with heavily pre-treated multiple myeloma. News release. Regeneron Pharmaceuticals, Inc; May 25, 2025. Accessed June 15, 2023. https://investor.regeneron.com/news-releases/news-release-details/updated-linvoseltamab-bcmaxcd3-data-pivotal-trial-demonstrates

Elranatamab (investigational)

Pooled data from the MagnetismMM studies were presented. In pts with RRMM and prior exposure to BCMA-directed therapies, elranatamab was efficacious and well tolerated; no new safety signals were observed vs the BCMA-naïve population. ORR = 45.3% (prior anti-BCMA therapy = 41%-53%); median time to OR = 1.9 months; complete response or better = 17.4%; duration of response at 9 months = 72% (prior anti-BCMA therapy = 67.3%-78%); median PFS = 4.8 months; median OS 10-month endpoint not reached, but = 60.1% at 9 months.

Treatment-emergent adverse events in all patients (and grade 3 or higher) included: CRS = 65% (1%); anemia = 59% (47%); neutropenia = 44% (41%); thrombocytopenia = 41% (29%); diarrhea = 34% (0%); lymphopenia = 33% (30%); and ICANS = 6% (2%).

Reference: Nooka AK, et al. Efficacy and safety of elranatamab in patients with relapsed/refractory multiple myeloma (RRMM) and prior B-cell maturation antigen (BCMA)-directed therapies: A pooled analysis from MagnetisMM studies. J Clin Oncol. 2023;41(16 suppl):8008. doi:10.1200/JCO.2023.41.16_suppl.8008