New Therapeutic Horizons for Advanced or Metastatic Penile Cancer - Beyond the Abstract

Penile cancer is a rare genitourinary (GU) malignancy with an annual incidence of just 36,000 cases globally and 2,000 cases in the U.S. Over 95% of these malignancies are squamous cell carcinomas. Platinum-based chemotherapy has been established as first-line therapy. However, survival is poor for patients with metastatic disease, particularly once it has progressed on first-line treatment. Thus, the need for novel therapeutics is essential for this vulnerable population.

Several therapeutic targets for penile cancer are currently being explored. Immune checkpoint inhibitors (ICIs) and ICI combination regimens have demonstrated promising results. Most recently, a phase I evaluation of cabozantinib and nivolumab with or without ipilimumab demonstrated an objective response rate (ORR) of 44% in 9 patients treated, prompting the ongoing phase II ICONIC study. The phase II HERCULES study also demonstrated an ORR of 39% with combination chemoimmunotherapy in the first-line setting for patients with metastatic penile cancer.

HPV-targeted therapies are another area of interest as approximately 50% of penile cancers are HPV-positive. Ongoing trials are exploring HPV-targeted therapeutic vaccines, often in combination with other immune-related agents. HPV-targeted T-cell receptor (TCR) therapies have also shown promise for patients with HPV-positive cancers. A phase I trial achieved partial responses in 6 of 12 patients and stable disease in an additional 4 patients treated with E7 TCR T cells.

Antibody-drug conjugates (ADCs) also hold promise. They consist of an antibody targeted to a cell-surface marker attached via a link to a cytotoxic payload. Nearly a quarter of penile cancers demonstrate HER2 2+/3+ staining, and trastuzumab deruxtecan (T-DXd) has demonstrated an ORR of 37% in HER2-positive solid tumors. High-risk HPV has also been associated with higher expression of nectin-4 and TROP-2, making enfortumab vedotin and sacituzumab govitecan other possible options. The SMART trial (NCT06161532) explores the use of TROP-2-directed ADC sacituzumab govitecan with or without atezolizumab in penile cancer and other rare GU malignancies.

While options are currently limited after first-line platinum-based chemotherapy, ongoing trials employing various therapeutic mechanisms and targets offer a promising outlook for patients with penile cancer. Multidisciplinary, collaborative care is imperative to moving the field forward and providing the best possible care to patients with penile cancer.

Written by:

  • Saad Atiq, MD, Department of Oncology, Genitourinary Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Magnuson Clinical Center, Bethesda, MD
  • Nicholas Simon, MD MSc, Department of Oncology, Genitourinary Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
  • Andrea Apolo, MD, Department of Oncology, Genitourinary Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Magnuson Clinical Center, Bethesda, MD
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