Systematic review of recent advancements in antibody-drug and bicycle toxin conjugates for the treatment of urothelial cancer.

Antibody-drug conjugates and bicycle toxin conjugates represent a tremendous advance in drug delivery technology and have shown great promise in the treatment of urothelial cancer. Previously approved systemic therapies, including chemotherapy and immunotherapy, are often impractical due to comorbidities, and outcomes for patients with advanced disease remain poor, even when receiving systemic therapy. In this setting, antibody-drug and bicycle toxin conjugates have emerged as novel treatments, dramatically altering the therapeutic landscape. These drugs harness unique designs consisting of antibody or bicycle peptide, linker, and cytotoxic payload with more targeted delivery than conventional chemotherapy, thus eliminating malignant cells while reducing systemic toxicities. Potential targets investigated in urothelial cancer include Nectin-4, TROP2, HER2, and EphA2. Initial clinical trials demonstrated efficacy in treatment of refractory advanced urothelial cancer, as well as improvement in quality of life. These initial studies led to FDA approval of two antibody-drug conjugates, enfortumab vedotin and sacituzumab govitecan. Moreover, antibody-drug and bicycle toxin conjugates are being studied in ongoing clinical trials in frontline treatment of advanced disease as well as for localized cancer. These studies highlight the potential for additional future therapies with novel targets, novel antibodies, cytotoxic and immunomodulatory payloads, and unique structural designs enhancing efficacy and safety. There is increasing evidence that combinations with other cancer therapies, especially immunotherapy, improve treatment outcomes. The combination of enfortumab vedotin and pembrolizumab was recently approved for first-line treatment of advanced urothelial carcinoma. Despite the great promise of these novel drugs, robust predictive biomarkers are needed to determine the patients who would maximally benefit. This review surveys the rationale and current state of the evidence for these new drugs and describes future directions actively being explored.

Review of recent advances in novel treatments of urothelial cancer Two new types of drugs, called antibody-drug conjugates (ADCs) and bicycle toxin conjugates (BTCs) have shown great promise in treating urothelial cancer. Both types of drugs consist of a structure targeting a specific protein on bladder cancer cells, linked to a drug that can kill cells. This allows for effective treatment of cancer with potentially less toxicity due to the targeted nature of these treatments. We discuss the potential targets in urothelial cancer and the drugs in these classes that could treat each target. Two of these drugs, enfortumab vedotin and sacituzumab govitecan, are in clinical use for cancers that have spread, while the others are in clinical trials. Moreover, the combination of enfortumab vedotin and pembrolizumab, an immunotherapy drug, has excellent results and was recently approved for first-line treatment of urothelial cancer that has spread. Additional studies are looking into these treatments for cancers that have not spread. In the future, management of side effects, determination of which patients benefit, and overcoming when the drugs become no longer effective will be important.

A Reappraisal of Definitive Chemoradiotherapy for Older Adults With Advanced Head and Neck Cancer.

BACKGROUND/AIM: Definitive treatment for locally advanced head and neck squamous cell carcinoma (LAHNSCC) is often compromised in older adults due to concerns about potential treatment toxicity intolerance. We reviewed our institutional experience with definitive management of older adults with LAHNSCC. PATIENTS AND METHODS: From our Institutional Review Board-approved registry, we identified patients aged >60 years with stage III-IV, M0 LAHNSCC (seventh/earlier editions of the American Joint Committee on Cancer classification) treated with definitive radiotherapy from 1993-2019. Indications for concurrent chemotherapy included T3-4 or N2-3 disease. Multivariable analysis using Fine and Gray regression was performed to identify risk factors associated with recurrence. The cumulative incidence method was used to calculate recurrence rates. RESULTS: Overall, 350 patients were identified: 223 aged 60-69, 82 aged 70-74, and 45 aged ≥75 years. Median follow-up was 36.3 months. Two-year recurrence rates were 13.7%, 20.2% and 34.8%, respectively; human papillomavirus-positive disease was present in 190 (85%), 44 (54%), and 25 (56%), respectively; and systemic therapy was given to 194 (87%), 64 (88%), and 23 (56%) patients, respectively. Factors significantly associated with increased risk of recurrence included age ≥75 years, Karnofsky performance status 70-80, clinical N2c-N3, and Charlson score 2-3. CONCLUSION: Patients aged ≥75 years received less aggressive therapy and experienced increased recurrence compared to younger patients. Outcomes for those aged 70-74 years were similar to younger patients treated with aggressive therapy, despite their inferior performance status/comorbidity, and such patients should not routinely be excluded from standard-of-care therapy. Further study is needed to optimize therapy for a redefined older adult (age ≥75 years) population.

Nasopharyngeal cancer: Incidence and prognosis of human papillomavirus and Epstein-Barr virus association at a single North American institution.

BACKGROUND: The prognostication of Epstein-Barr virus (EBV) and human papillomavirus (HPV) status in nasopharyngeal cancer (NPC) is unclear. METHODS: This retrospective study analyzed NPC from 2000 to 2019. RESULTS: Seventy-eight patients were included: 43 EBV+ , 12 HPV+ , 23 EBV- /HPV- , and 0 EBV+ /HPV+ . All p16+ tumors were also positive for HPV-CISH. Baseline characteristics were not different between groups except age, N-classification, and Karnofsky Performance Scale (KPS) (p < 0.05). For EBV+ , HPV+ , and EBV- /HPV- respectively, 3-year overall survival (OS) was 89.9%, 69.8%, and 52.5% (p = 0.006). EBV- /HPV- status was significantly associated with worse OS but not freedom from progression (FFP) on univariate analysis, and did not remain a significant predictor of OS after adjusting for KPS, age, and group stage. CONCLUSIONS: EBV+ NPC tumors were seen in younger, healthier patients than HPV+ and EBV- tumors, and there were no cases of coinfection. The association of viral status with OS was insignificant after adjusting for KPS and age.

Updated Outcomes of Split Course Radiotherapy in Elderly or Infirm Patients With Advanced Cancers of the Head and Neck.

BACKGROUND/AIM: Head and neck cancers are often treated with extended courses of radiotherapy (RT), which may prove excessively toxic for frail patients. Split course RT (SCRT) delivers two courses of RT separated by 4-6 weeks, personalizing treatment intensity based on response. In this study, we present our updated experience using this technique. PATIENTS AND METHODS: From a single institution database, we identified patients considered for SCRT. For patients undergoing a second course of RT, cumulative incidence of locoregional recurrence (LRR) and overall survival (OS) are reported. RESULTS: A total of 98 patients were included, of whom seventy-five percent underwent a second course of RT. The most common fractionation was 30 Gy in 10 fractions for each course, with a median cumulative dose of 60 Gy. In those undergoing a second course of RT, median OS was 9.7 months and cumulative incidence of LRR at 6, 12, and 24 months was 17.0%, 23.1%, and 29.4%, respectively. CONCLUSION: SCRT offers an attractive treatment paradigm to personalize radiation intensity based on patient tolerance, while maintaining reasonable safety and efficacy in those unfit for standard full course RT.

A sheep model of cystic fibrosis generated by CRISPR/Cas9 disruption of the CFTR gene.

Cystic fibrosis (CF) is a genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. The major cause of limited life span in CF patients is progressive lung disease. CF models have been generated in 4 species (mice, rats, ferrets, and pigs) to enhance our understanding of the CF pathogenesis. Sheep may be a particularly relevant animal to model CF in humans due to the similarities in lung anatomy and development in the two species. Here, we describe the generation of a sheep model for CF using CRISPR/Cas9 genome editing and somatic cell nuclear transfer (SCNT) techniques. We generated cells with CFTR gene disruption and used them for production of CFTR-/- and CFTR+/- lambs. The newborn CFTR-/- sheep developed severe disease consistent with CF pathology in humans. Of particular relevance were pancreatic fibrosis, intestinal obstruction, and absence of the vas deferens. Also, substantial liver and gallbladder disease may reflect CF liver disease that is evident in humans. The phenotype of CFTR-/- sheep suggests this large animal model will be a useful resource to advance the development of new CF therapeutics. Moreover, the generation of specific human CF disease-associated mutations in sheep may advance personalized medicine for this common genetic disorder.