Johnson & Johnson stock: 73% PSA response supports Phase 3 test

Johnson & Johnson reported on November 9 that an investigational dual-bispecific antibody regimen produced encouraging early responses in advanced prostate cancer. The company's press release said 11 of 15 patients at the recommended regimen achieved a prostate-specific antigen reduction of at least 50% in a Phase 1 study. At 2:30 p.m. CET on Wednesday, November 11, Johnson & Johnson stock traded at 250.13 euros on Lang & Schwarz, 0.78% below the Xetra close of 252.10 euros on Tuesday, November 10.

Two signals target prostate cancer

The combination pairs pasritamig, a KLK2xCD3 bispecific antibody, with JNJ-9401, a PSMAxCD28 costimulatory bispecific antibody. Johnson & Johnson says the medicines are designed to direct T cells toward prostate-cancer cells and provide a complementary activation signal.

The results were presented at the Society for Immunotherapy of Cancer 2026 Annual Meeting. The company described the regimen as the first dual-tumor-antigen-targeted bispecific antibody combination clinically evaluated in prostate cancer. The findings apply to metastatic castration-resistant prostate cancer, a disease that continues to progress despite treatment aimed at the androgen receptor pathway.

The recommended regimen produced reductions of at least 90% in seven of the 15 patients, while four reached undetectable PSA levels. All seven patients with reductions of at least 90% remained on treatment for more than six months without disease progression. These results are early signals rather than evidence of established clinical benefit, because the analysis covers a small group at one dose level.

Safety profile supports further testing

Johnson & Johnson reported no Grade 3 or higher treatment-related adverse events, dose-limiting toxicities, treatment-related discontinuations or treatment-related deaths at the recommended regimen. Cytokine release syndrome occurred in three patients, or 20%, and all cases were Grade 1; no patient required tocilizumab. No cases of immune effector cell-associated neurotoxicity syndrome were reported.

The study had enrolled 144 patients by June 15, 2026, although the response analysis focused on 15 patients treated at the recommended regimen. Those patients had received a median of four prior systemic therapies, making the observed activity notable but also underscoring the need for confirmation in a larger population.

Phase 3 becomes the next catalyst

The combination is now being evaluated in the Phase 3 KLK2-comPAS study, which is testing whether adding JNJ-9401 to pasritamig improves outcomes for patients with metastatic castration-resistant prostate cancer. A second Phase 3 program, KLK2-PASenger, is evaluating pasritamig with docetaxel in first-line disease. The dosing schedule uses JNJ-9401 every six weeks and pasritamig every six weeks after two initial weekly step-up doses, a structure the company says could support outpatient treatment.

For investors, the key issue is whether PSA reductions translate into measurable improvements in disease control and survival. The early safety profile and the depth of the responses support continued development, but Phase 3 results will carry considerably more weight for the value of Johnson & Johnson's oncology pipeline. The company also remains exposed to the usual risks of investigational medicine development, including unsuccessful trials and regulatory setbacks.

Johnson & Johnson stock facts

• Company: Johnson & Johnson
• ISIN: US4781601046
• Home exchange: New York Stock Exchange
• Lang & Schwarz: 250.13 euros at 2:30 p.m. CET on November 11, 2026
• Daily comparison: 0.78% below the Xetra close of 252.10 euros on November 10, 2026
• Sector: Healthcare
• Industry: Drug Manufacturers - General

Healthcare investors can follow broader market developments in the S&P 500.

For the company's latest developments, see More news and analyses on Johnson & Johnson stock.

Source: Johnson & Johnson press release.