What's Going On with Bristol Myers Squibb Stock on Friday?

Bristol Myers Squibb & Co. (NYSE:BMY) stock is trading lower on Friday after the company reported one patient death in an investigational CD19-directed CAR T cell therapy trial.

At the MSToronto 2026 conference in Toronto, the pharmaceutical company presented interim findings from the Breakfree-2 trial testing zolacabtagene autoleucel (zola-cel), an investigational CD19-directed CAR T cell therapy.

CAR T Therapy Demonstrates Immune Reset In Multiple Sclerosis

The single-arm Breakfree-2 trial enrolled 66 participants with highly active relapsing or progressive multiple sclerosis whose disease advanced despite a median of two prior disease-modifying therapies.

All 60 patients receiving dose level 2 remained completely off standard treatments at their last follow-up, with nine patients exceeding 12 months without treatment.

Among evaluable patients followed for 26 weeks or more, six of seven relapsing multiple sclerosis patients achieved no evidence of disease activity.

In addition, 92% of progressive patients showed stability or improvement in disability progression, and all 24 evaluable progressive patients showed zero new MRI activity.

Most adverse events resolved quickly, although 42.4% experienced cytokine release syndrome.

One patient died from septic pneumonia 44 days post-infusion following cyclophosphamide treatment for motor complications, marking the only fatal event across 190 autoimmune trial participants.

Bispecific ADC Cuts Breast Cancer Progression Risk By 59%

In Madrid at the ESMO 2026 congress, Bristol Myers Squibb and partner SystImmune presented Phase 3 PANKU-Breast01 data simultaneously published in The Lancet.

Sponsored by Sichuan Biokin Pharmaceutical, the trial evaluated izalontamab brengitecan (iza-bren), an investigational dual-targeting EGFRxHER3 bispecific antibody-drug conjugate, against chemotherapy in pretreated HR-positive, HER2-negative metastatic breast cancer.

Iza-bren reduced the risk of disease progression or death by 59% compared to chemotherapy, extending median progression-free survival to 8.2 months from 4.0 months.

The drug conjugate doubled the confirmed objective response rate to 40.5% versus 20.2% and lengthened median response duration to 6.9 months from 4.2 months. Outside China, Bristol Myers Squibb and SystImmune are co-developing the therapy across five Phase 3 indications.

BMY Price Action: Bristol-Myers Squibb shares were down 2.17% at $61.63 at the time of publication on Friday, according to Benzinga Pro data.

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