Long term outcomes of phase I/II study of palliative triple metronomic chemotherapy in platinum-refractory/early failure oral cancer

Background

Triple metronomic chemotherapy is one of the options of treatment in platinum-refractory/early failure oral cancer. However, long term outcomes with this regimen are unknown.

Methods

Adult patients with platinum-refractory/early-failure oral cancer were enrolled in the study. Patients were administered triple metronomic chemotherapy ie erlotinib 150 mg once daily celecoxib 200 mg twice daily and methotrexate weekly (phase 1 in variable dose 15-6 mg/m² & 9 mg/m² in phase 2), all taken orally till progression of disease or development of intolerable adverse events. The primary objective was to estimate the long-term overall survival and factors impacting it. The Kaplan Meier method was used for time-to-event analysis. Cox proportional hazard model was used to identify factors impacting overall survival (OS) and progression-free survival (PFS). The factors included in the model were age, sex, Eastern Cooperative Oncology Group - performance status (ECOG PS), tobacco exposure and a subsite of primary and circulating endothelial cell levels at baseline. A p-value of 0.05 was considered significant. Clinical trials information: CTRI/2016/04/006834.

Results

A total of 91 patients were recruited (15 in phase 1 & 76 in phase 2), the median follow-up was 41 months and 84 events of death had occurred. The median OS was 6.7 months (95% CI 5.4-7.4). The 1-year, 2-years and 3-year OS' were 14.1% (95% CI 7.8-22.2), 5.9% (95% CI 2.2-12.2) and 5.9% (95% CI 2.2-12.2) respectively. The only factor favorably impacting OS was the detection of circulating endothelial cells at baseline (HR = 0.46; 95% CI 0.28-0.75, P = 0.0020). The median PFS was 4.3 months (95% CI 4.1-5.1) and the 1-year PFS was 13.0% (95% CI 6.8-21.2). The factors with statistically significant impact on PFS were detection of circulating endothelial cells at baseline (HR = 0.48; 95% CI 0.30-0.78, P = 0.0020) and no tobacco exposure at baseline (HR = 0.51; 95% CI 0.27-0.94, P = 0.030).

Interpretation

The long-term outcomes with triple oral metronomic chemotherapy ie erlotinib, methotrexate and celecoxib are unsatisfactory. Detection of circulating endothelial cells at baseline is a biomarker predicting efficacy of this therapy.

Funding

The study was funded by an intramural grant from Tata Memorial Center Research Administration Council (TRAC) and Terry Fox foundation.

Results of phase 3 randomized trial for use of docetaxel as a radiosensitizer in patients with head and neck cancer unsuitable for cisplatin-based chemoradiation

LBA6003

Background: Systemic therapy options have not been systematically evaluated in cisplatin-ineligible locally advanced head and neck squamous cell carcinoma (LAHNSCC) patients undergoing chemoradiation. This study evaluated docetaxel as a radiosensitizer in this setting. Methods: This was a randomised open-label study. Adults with LAHNSCC planned for radical or adjuvant chemoradiation, with ECOG PS 0-2 and who were cisplatin-ineligible as per the criteria by Ahn et al were enrolled. The patients were randomly assigned 1:1 to receive radiation alone or radiation with concurrent docetaxel 15 mg/m2 weekly for a maximum of 7 cycles. Adverse events were recorded in accordance with CTCAE version 4.03. The FACT-G, and H and N questionnaires (version 4) were self-administered at baseline, 6 months, 12 months and at 24 months. The primary endpoint was disease-free survival (DFS) and key secondary endpoints were overall survival (OS), adverse events and quality of life (Trial outcome index (TOI)). Results: The study recruited 356 patients with 176 in RT and 180 in the docetaxel-RT arm. The 2-year DFS was 30.3% (95%CI 23.6-37.4) versus 42% (95%CI 34.6-49.2) in the RT and docetaxel-RT arms respectively (Hazard ratio- 0.673; 95% CI 0.521-0.868; P-value=0.002). The median overall survival (OS) was 15.3 months (95%CI 13.1-22) in the RT arm and 25.5 months (95% CI 17.6-32.5) in the docetaxel-RT arm. (Log-rank P-value =.0.035). The 2 -year OS was 41.7% (95%CI 34.1-49.1) versus 50.8% (95%CI 43.1-58.1) in the RT and docetaxel-RT arms respectively (Hazard ratio-0.747; 95% CI 0.569-0.98; P-value=0.035). Any grade 3 or above adverse events were seen in 102 patients (58%) in RT and in 146 (81.6%) in docetaxel-RT arms respectively (P-value=0.000). There was a higher incidence of grade 3 and above mucositis (22.2% versus 49.7%; P<0.001), odynophagia (33.5% versus 52.5%; P<0.001) and dysphagia (33% versus 49.7%; P<0.002) with the addition of docetaxel. The addition of docetaxel did not lead to a worsening of TOI scores and FACT-G scores at 6 months. Conclusions: The addition of docetaxel to radiation improved disease-free survival and overall survival in cisplatin-ineligible LAHNSCC and represents a new standard of care. Clinical trial information: CTRI/2017/05/008700.

Phase 3 randomised study evaluating the addition of low-dose nivolumab to palliative chemotherapy in head and neck cancer

LBA6016

Background: The regimens approved for the treatment of advanced head and neck squamous cell carcinoma (HNSCC) are accessible to only 1-3% of patients in low and middle-income countries due to cost. In our previous study, metronomic chemotherapy (MC) improved survival in this setting. Retrospective data suggest that a low dose of nivolumab may be efficacious. Hence, we aimed to assess whether the addition of low dose nivolumab to MC improved the overall survival. Methods: This was a randomised phase 3 superiority open-label study. Adult patients with relapsed -recurrent or newly diagnosed advanced HNSCC being treated with palliative intent with ECOG PS 0-1 were eligible. Patients were randomised 1:1 to MC consisting of methotrexate 15 mg/m2 PO weekly, celecoxib 200 mg PO daily and erlotinib 150 mg PO daily, or MC with intravenous nivolumab 20 mg flat dose once-every-3-weeks. Therapy was continued until disease progression or intolerable adverse events. Response assessment (RECIST version 1.1) was performed every 2 months. The primary endpoint was 1-year overall survival (OS) and this was a pre-specified interim analysis with the nominal p-value for efficacy being 0.006. Results: 151 patients were randomised, 75 in MC and 76 in the MC-I arm respectively. The addition of low dose nivolumab led to an improvement in the 1-year overall survival from 16.3% (95%CI 7.95-27.4) to 43.4% (95% CI 30.8-52.3) [Hazard ratio-0.545; 95%CI 0.362-0.82; P=0.00358]. The median overall survival in MC and MC-I arms was 6.7 months (95%CI 5.83 -8.07) and 10.1 months (95%CI 7.37-12.63) respectively (P=0.0052). The median progression-free survival in MC and MC-I arms was 4.57 months (95%CI 4.2 -5.3) and 6.57 months (95%CI 4.43-8.9) respectively (P=0.0021). Response rate in MC and MC-I arm were 49.3% (95% CI 37.8-60.8) and 65.2% (95%CI 53.4-75.4) respectively (P=0.085). The rate of grade 3 and above adverse events was 50% and 46.1% in MC and MC-I arm respectively (P=0.744). Conclusions: In this first-ever randomised study, the addition of low dose nivolumab led to improved overall survival and is an alternative standard of care for those who cannot access full dose nivolumab. Clinical trial information: CTRI/2020/11/028953.

Five years survival outcomes of head and neck cancer patients treated with palliative metronomic chemotherapy

e18009

Background: Palliative metronomic chemotherapy improved overall survival over intravenous chemotherapy in head and neck cancers. However, there is no data available about the 5-year outcomes with this regimen. Methods: This was a single-arm prospective study that enrolled head and neck squamous cell carcinoma patients warranting palliative chemotherapy. The chemotherapy administered was methotrexate 15 mg/m2 per oral weekly and celecoxib 200 mg per oral daily till the development of intolerable side effects or progression. Kaplan Meier method was used for estimation of OS and factors impacting the same were sought. A p-value of 0.05 was considered significant. Results: 200 patients were enrolled with a median age was 49.5 years (Range 22-85 years) and preponderance of male gender (175, 87.5%). The predominant site of malignancy was oral cavity in 144 patients (72.2%). Prior chemotherapy exposure was present in 78 patients (39%). The median FACT trial outcome index score was 43.7 (16.7-80.7). The median OS was 194 days (95%CI 181.7-206.3) . The 1-year, 3-years and 5-years OS were 17 %(Standard error-2.8%), 7.9% (Standard error-2.5%), and 3.9% (Standard error- 2%) respectively. The details of factors impacting OS are given in Table. Conclusions: Oral metronomic chemotherapy leads to a small proportion of patients having long term survival with metronomic chemotherapy. Clinical trial information: CTRI/2015/11/006392. [Table: see text]

Phase III randomized control study evaluating adjuvant metronomic chemotherapy in locally advanced head and neck cancers post-radical chemoradiation (MACE-CTRT)

6073

Background: Locally advanced head and neck cancer treated with radical chemoradiation have unsatisfactory outcomes. Oral metronomic chemotherapy improves outcomes in comparison to maximum tolerated dose chemotherapy in the palliative setting. There is also limited evidence that it may do so in an adjuvant setting. Hence this randomised study was conducted. Methods: Patients of HN cancer with primary in oropharynx, larynx or hypopharynx, with PS 0-2 post radical chemoradiation with documented complete response were 1:1 randomised to either observation or oral metronomic adjuvant chemotherapy (MAC) for 18 months. MAC consisted of weekly oral methotrexate (15 mg/m2) and celecoxib (200 mg PO BD). The primary endpoint was OS and the overall sample size was 1038. The study had 3 planned interim analyses for efficacy and futility. Results: 137 patients were recruited and an interim analysis was done. The 3 year PFS in the observation arm was 67.1% (95% CI 53.8-77.3) and the same in the MAC arm was 62.5%(95%CI 49.4-73.1). The corresponding hazard ratio was 1.402 (95% CI 0.7393-2.66, P-value = 0.3). The 3 year OS in the observation arm was 77.3% (95% CI 64.4-86) and the same in the MAC arm was 64.1% (95%CI 51-74.5). The corresponding hazard ratio was 1.588 (95% CI 0.8734-2.886, P-value = 0.1). Any grade mucositis was seen in 30 patients (45.5%) in the MAC arm and 20 patients (28.2%) in the observation arm (P-value = 0.05). The rate of grade 3 or above mucositis was 7.6%(n = 5) in the MAC arm and 1.4%(n = 1) in the observation arm (P-value = 0.106). Conclusions: Both arms had similar OS. Hence observation post complete response post radical chemoradiation remains the standard of care. Clinical trial information: CTRI/2016/09/007315.

Long-term outcomes of a randomized controlled clinical trial comparing the efficacy of cabazitaxel versus docetaxel as second-line or above therapy in recurrent head and neck cancer

e18008

Background: Long term outcomes (> 2 years or above) are rarely reported in studies with second line or beyond systemic therapies in head and neck squmouas cell carcinoma (HNSCC). Methods: Recurrent or relapsed adult HNSCC, with ECOG PS 0-2 who have been exposed to at least one line of chemotherapy were 1:1 randomized between Docetaxel (75 mg/m2) and Cabazitaxel (20 mg/m2). The chemotherapy was given till progression or development of intolerable side effects. The outcomes reported are long term overall survival(OS) and progression free survival (PFS) and factors impacting overall survival. Results: On the intention to treat analysis (n = 92), at the time of data censoring, 92 patients had died. The median overall survival was 112 days (95% CI 81 to 178 days) in the cabazitaxel arm versus 192 days (95% CI 153 to 259 days) in the Docetaxel arm (P = 0.048). In cabazitaxel arm, the one year OS was 6.5% (95% CI 1.6-16.06), 2 year OS was 2.17% (95% CI 0.17-9.95) and 3 years was 2.17% (95% CI 0.17-9.95). While the corresponding figures in the docetaxel arm were 21.7% (95% CI 11.23-34.46), 0% and 0%. The median progression-free survival was 21.0 days (95% CI 16.0-42.0 days) in the Cabazitaxel arm versus 57.5 days (95% CI 26.0-85.0 days) in the Docetaxel arm (P = 0.02). Among the tested factors age (p = 0.037) and site of primary(p = 0.023) had an impact on OS. Conclusions: In this phase 2 randomised study, cabazitaxel has inferior PFS and OS than docetaxel. Hence docetaxel remains the option of choice when cytotoxic chemotherapy needs to be used as second line or beyond setting in HNSCC. Clinical trial information: CTRI/2015/06/005848.

Long-term outcomes of phase I/II study of palliative triple metronomic chemotherapy in platinum-refractory/early failure oral cancer

e18021

Background: Triple metronomic chemotherapy is one of the options of treatment in platinum-refractory/early failure oral cancer. However long term outcomes with this regimen are unknown. Methods: Adult patients with platinum-refractory/early failure oral cancer were enrolled in the study. Patients were administered erlotinib 150 mg once daily celecoxib 200 mg twice daily and methotrexate weekly (phase 1 in variable dose 15-6 mg/m2 & 9 mg/m2 in phase 2), all taken orally till progression of disease or development of intolerable adverse events. The primary objective was to estimate the long term overall survival and factors impacting it. Kaplan Meier method was used for time to event analysis. COX proportional hazard model was used to identify factors impacting OS and PFS. The factors included in the model were age, gender, ECOG PS, tobacco exposure, a subsite of primary and circulating endothelial cell levels at baseline. A p-value of 0.05 was considered significant. Results: A total of 91 patients were recruited (15 in phase 1 & 76 in phase 2), the median follow-up was 41 months and 84 events of death had occurred. The median OS was 6.67 months (95%CI 5.43-7.37). The 1-year, 2-years and 3-years OS were 14.07% (95%CI 7.75-22.2), 5.86% (95%CI 2.18-12.2) and 5.86% (95%CI 2.18-12.2) respectively. The only factor favourably impacting OS was the detection of circulating endothelial cells at baseline (HR = 0.459; 95%CI 0.28 -0.753, P = 0.002). The median PFS was 4.3 months (95%CI 4.1-5.1) and the 1-year PFS was 12.97% (95%CI 6.8-21.2). The factors with statistically significant impact on PFS were detection of circulating endothelial cells at baseline (HR = 0.479; 95%CI 0.3 -0.775, P = 0.002) and tobacco exposure at baseline (HR = 0.505; 95%CI 0.272 -0.937, P = 0.03). Conclusions: The long term outcomes with triple oral metronomic chemotherapy with erlotinib, methotrexate and celecoxib are unsatisfactory. Detection of circulating endothelial cells at baseline is a biomarker predicting efficacy of this therapy. Clinical trial information: CTRI/2016/04/006834..

Six-year follow-up from the weekly-three-weekly study comparing cisplatin once-a-week to once-every-three-weeks as concurrent chemoradiation for locally advanced head and neck squamous cell carcinoma

6071

Background: In the weekly-3-weekly (W3W) study, cisplatin at 100 mg/m2 once-every-3-weeks led to superior locoregional control compared to cisplatin 30 mg/m2 once-a-week in combination with radical radiation for locally advanced head and neck squamous cell carcinoma (LAHNSCC). We report the updated analysis of the study. Methods: In this phase III open label non-inferiority study conducted between 2013 and 2017, 300 patients with LAHNSCC were randomly assigned to receive cisplatin 100 mg/m2 once-in-3-weeks or cisplatin 30 mg/m2 once-a-week, concurrently with radiation. The primary endpoint was locoregional control. Secondary outcomes included progression free survival (PFS), overall survival (OS), toxicity, and quality of life. Results: As of February 5, 2022 (median follow-up, 77.3 months), 132 patients (44%) have had an event for locoregional recurrence; 75 (50%) in the once-a-week cisplatin arm and 57 (38%) in the once-every-3-weeks cisplatin arm. The updated estimated cumulative 2-year locoregional control rates were 59.3% and 75.3% in the once-a-week and once-every-3-weeks cisplatin arms, respectively; absolute difference, 16% (95% CI, 7.19 to 24.81). The estimated 5-year locoregional control rates were 48.2% and 55.2% in the once-a-week and once-every-3-weeks cisplatin arms respectively; absolute difference, 7% (95% CI, -2.5 to 16.5). The median time to locoregional failure was 46.1 months (95% CI, 31.63 to 60.56) in the once-a-week cisplatin arm, and 57.9 months (95% CI, 47.1 to 68.6) in the once-every-3-weeks cisplatin arm; HR, 1.43 (95% CI, 1.01 to 2.02); P = 0.042. The estimated median PFS was 17.5 months (95% CI, 0 to 38.31) in the once-a-week cisplatin arm, versus 37.5 months (95% CI, 28.45 to 46.45) in the once-every-3-weeks cisplatin arm; HR, 1.13 (95% CI, 0.85 to 1.5); P = 0.41. Events for OS included 173 (57.7%) deaths; 109 (36.3%) patients are alive, and 18 (6%) are lost to follow-up. The 5-year OS in the once-a-week and once-every-3-weeks cisplatin arms were 43.1% and 48.6%, respectively. Estimated median OS was 38.5 months (95% CI, 16.3 to 60.7) in the once-a-week cisplatin arm, versus 57.3 months (95% CI, 38.6 to 75.9) in the once-every-3-weeks cisplatin arm; HR, 1.19 (95% CI, 0.89 to 1.6); P = 0.238. Details regarding chronic toxicities and second primaries will be presented. Conclusions: Long term follow-up confirms that cisplatin at 100 mg/m2 administered once-every-3-weeks concurrently with radical radiation for LAHNSCC leads to superior locoregional control and should remain the standard of care. The study was not powered to test for a difference in OS; OS was numerically higher in the once-every-3-weeks cisplatin arm, but the difference did not attain statistical significance. Clinical trial information: CTRI/2012/10/ 003062.