Platinum resistance and sensitivity in recurrent/metastatic head and neck squamous cell carcinoma

OBJECTIVE

For patients with recurrent/metastatic head and neck squamous cell carcinoma (R/MHNSCC), platinum-free interval (PFI)-based differences in the effectiveness of rechallenge with platinum-based chemotherapy (PBCT) remain unknown. We aimed to evaluate the difference in platinum sensitivity based on PFI in R/MHNSCC.

METHODS

We retrospectively examined 80 patients with R/MHNSCC who underwent PBCT between 2001 and 2020. Treatment efficacy was compared between patients with prior PBCT for treatment of recurrence/metastasis or concurrent chemoradiotherapy during radical treatment (rechallenge group) and those without (control group). Patients with prior PBCT (rechallenge group) were stratified by PFI. PFI was defined as the period from the last dosing date with the previous platinum agent to rechallenge with PBCT.

RESULTS

Of 80 patients, 55 had been with prior PBCT (rechallenge group) and 25 had been without prior PBCT (control group). The rechallenge group was divided into three groups: PFI <6 months (10), PFI 6-11 months (17), and PFI ≥12 months (28). The PFI <6-month group had shorter overall survival (p=0.047, the log-rank test) and lower disease control rate (p=0.02, Fisher's exact test) than the control group. The PFI 6-11- and ≥12-month group outcomes did not significantly differ from those of the control group.

CONCLUSIONS

Patients with PFI <6 months tend to have a poorer prognosis after rechallenge with PBCT than patients without prior PBCT, suggesting that PFI 6 months may be considered as a threshold of platinum resistance and rechallenge with PBCT may be a valid option in PFI ≥6 months.

A phase 1b study of trebananib in combination with pegylated liposomal doxorubicin or topotecan in women with recurrent platinum-resistant or partially platinum-sensitive ovarian cancer

OBJECTIVE

To examine the tolerability and antitumor activity of trebananib plus pegylated liposomal doxorubicin (PLD) or topotecan in recurrent platinum-resistant or partially platinum-sensitive ovarian cancer.

METHODS

In this open-label phase 1b study, patients received trebananib 10 mg/kg or 15 mg/kg IV QW plus PLD 50 mg/m(2) (cohorts A1 and A3, respectively) or topotecan 4 mg/m(2) (cohorts B1 and B3, respectively). Endpoints were dose-limiting toxicity (DLT; primary); treatment-emergent adverse events (AEs), overall response rate, anti-trebananib antibodies, and pharmacokinetics (secondary).

RESULTS

103 patients were enrolled. One patient in A1 and B1 had DLTs. Across all cohorts, the most common AEs were nausea, fatigue, and peripheral edema. Across both trebananib plus PLD cohorts (A1/A3), grade 4 AEs were pulmonary embolism, disease progression, and anemia. Two patients had grade 5 intestinal perforation (n=1) and sudden death (n=1). Across both trebananib plus topotecan cohorts (B1/B3), grade 4 AEs were neutropenia, hypokalemia, decreased granulocyte count, chest pain, dyspnea, decreased neutrophil count, and pulmonary embolism. Two patients had grade 5 disease progression. One patient had grade 5 pleural effusion associated with progressive disease. Confirmed objective response rates were 36.0% (A1), 34.8% (A3), 16.7% (B1), and 0.0% (B3). Median progression-free survival duration (months) was 7.4 (A1), 7.1 (A3), 3.5 (B1), and 3.1 (B3), respectively. No drug-drug interactions were apparent.

CONCLUSIONS

Trebananib 10mg/kg and 15 mg/kg IV QW plus PLD or topotecan appear to have acceptable toxicity profiles in recurrent platinum-resistant or partially platinum-sensitive ovarian cancer. Antitumor activity was evident across all cohorts.

Trabectedin plus pegylated liposomal doxorubicin in the treatment of patients with partially platinum-sensitive ovarian cancer: current evidence and future perspectives

The effectiveness of platinum re-treatment in relapsed ovarian cancer depends on relapse-free/treatment-free intervals. Platinum agents can be effectively readministered to platinum-sensitive patients (relapsing >12 months after platinum), but efficacy is lower in partially platinum-sensitive (PPS) disease (relapsing 6-12 months after platinum). There is no clear standard treatment challenging PPS patients. Survival data in this subset with chemotherapy combinations such as pegylated liposomal doxorubicin (PLD) plus carboplatin or gemcitabine plus PLD are available from phase II trials ranging from 16 to 21 months. Recent results from OVA-301 phase III randomized trial evaluating trabectedin plus PLD showed the longest median overall survival ever reported in PPS patients (23 months). Subsequent chemotherapy (including platinum-based regimens) was administered later and survival in patients receiving third-line platinum was longer in patients treated with trabectedin plus PLD compared with those treated with PLD alone. These results suggest that prolonging platinum-free interval (PFI) with an effective non-platinum regimen improves outcome with subsequent third-line platinum treatment. An ongoing phase III trial (INOVATYON) aims to demonstrate if the results observed with trabectedin plus PLD in PPS patients are due to PFI extension, and if PFI extension with non-platinum combination prolongs response to subsequent platinum and survival in this population.