Feasibility of using a pragmatic trials model to compare two primary febrile neutropenia prophylaxis regimens (ciprofloxacin versus G-CSF) in patients receiving docetaxel-cyclophosphamide chemotherapy for breast cancer (REaCT-TC)

Oral magnesium supplements for cancer treatment-induced hypomagnesemia: Results from a pilot randomized trial

BACKGROUND AND AIMS

Optimal management of cancer treatment-induced hypomagnesemia (hMg) is not known. We assessed the feasibility of using a novel pragmatic clinical trials model to compare two commonly used oral Mg replacement strategies.

METHODS

Patients with grade 1 to 3 hMg while receiving either platinum-based chemotherapy or epidermal growth factor receptor inhibitors (EGFRI) were randomized to oral magnesium oxide (MgOx) or oral magnesium citrate (MgCit). The trial methodology utilized the integrated consent model. Feasibility would be successful if; accrual rate was ≥5 patients a month and if measures of patient and physician engagement, were > 50%. Secondary endpoints included; comparison of Mg levels, cardiac arrhythmias, and rates of treatment delay/hospitalizations.

RESULTS

From July 2016 to December 2017, an average of 1 patient a month was accrued. All 15 eligible and approached patients consented to participate in the study (100% engagement) and 7/15 were randomized to MgOx and 8/15 to MgCit. The percentage of physicians who approached patients for the study was 4 of 6 (66.6% engagement). The mean slope of change in Mg (mmol/L/day) was 0.0022 (95% CI: -0.0001 to 0.0044) for MgOx and 0.0006 (95% CI, -0.0012 to 0.0024) for MgCit (P = .2123). Three patients (20%) required IV magnesium while on the study (2 MgCit and 1 MgOx). Grade 1 diarrhea occurred in 3 patients in the MgCit arm.

CONCLUSION

Despite oral magnesium tolerability and meeting most of its feasibility endpoints, this study did not meet its target accrual rate. Alternative designs would be necessary for a definitive efficacy study.

The Rethinking Clinical Trials (REaCT) Program. A Canadian-Led Pragmatic Trials Program: Strategies for Integrating Knowledge Users into Trial Design

We reviewed patient and health care provider (HCP) surveys performed through the REaCT program. The REaCT team has performed 15 patient surveys (2298 respondents) and 13 HCP surveys (1033 respondents) that have addressed a broad range of topics in breast cancer management. Over time, the proportion of surveys distributed by paper/regular mail has fallen, with electronic distribution now the norm. For the patient surveys, the median duration of the surveys was 3 months (IQR 2.5-7 months) and the median response rate was 84% (IQR 80-91.7%). For the HCP surveys, the median survey duration was 3 months (IQR 1.75-4 months), and the median response rate, where available, was 28% (IQR 21.2-49%). The survey data have so far led to: 10 systematic reviews, 6 peer-reviewed grant applications and 19 clinical trials. Knowledge users should be an essential component of clinical research. The REaCT program has integrated surveys as a standard step of their trials process. The COVID-19 pandemic and reduced face-to-face interactions with patients in the clinic as well as the continued importance of social media highlight the need for alternative means of distributing and responding to surveys.

A multi-centre study comparing granulocyte-colony stimulating factors to antibiotics for primary prophylaxis of docetaxel-cyclophosphamide induced febrile neutropenia

BACKGROUND

Primary febrile neutropenia (FN) prophylaxis with ciprofloxacin or granulocyte-colony stimulating factors (G-CSF) is recommended with docetaxel-cyclophosphamide (TC) chemotherapy for early-stage breast cancer (EBC). A pragmatic randomised trial compared the superiority of G-CSF to ciprofloxacin and a cost-utility analysis were conducted.

METHODS

EBC patients receiving TC chemotherapy were randomised to ciprofloxacin or G-CSF. The primary outcome was a composite of FN and non-FN treatment-related hospitalisation. Secondary outcomes included; rates of FN, non-FN treatment-related hospitalisation, chemotherapy dose reductions/delays/discontinuations. Primary analysis was performed with the intention to treat population. Cost-utility analyses were conducted from the Canadian public payer perspective.

RESULTS

458 eligible patients were randomised: 228 to ciprofloxacin and 230 to G-CSF. For the primary endpoint there was non-statistically significant difference (Risk difference = -6.7%, 95%CI = -13.5%-0.1%, p = 0.061) between ciprofloxacin patients (46,20.2%) and G-CSF (31,13.5%). Patients receiving ciprofloxacin were more likely to experience FN (36/228, 15.8% vs 13/230, 5.7%) than patients receiving G-CSF (p < 0.001). Non-FN treatment-related hospitalisation occurred in 40/228 (17.5%) of ciprofloxacin patients vs 28/230 (12.2%) of G-CSF patients (p = 0.12). There were no differences in other secondary outcomes. G-CSF was associated with an incremental cost-effectiveness ratio of C$1,760,796 per one quality-adjusted life year gained.

CONCLUSION

The primary endpoint of superiority of G-CSF over ciprofloxacin was not demonstrated. While there were reduced FN rates with G-CSF, there were no differences in chemotherapy dose delays/reductions or discontinuations. With the commonly used willingness to pay value of C$50,000/QALY, G-CSF use was not cost-effective compared to ciprofloxacin and deserves scrutiny from the payer perspective.

A prospective multi-centre, randomized study comparing the addition of tapering dexamethasone to other standard of care therapies for taxane-associated pain syndrome (TAPS) in breast cancer patients

PURPOSE

Taxane-associated pain syndrome (TAPS) is common with docetaxel and is characterised by myalgias and arthralgias starting 2-3 days after treatment and can last for up to 7 days. Anecdotal evidence suggests that corticosteroids can reduce TAPS. This multicentre, randomized trial evaluated the effect of additional tapering dexamethasone on TAPS.

METHODS

130 breast cancer patients commencing docetaxel were randomized to dexamethasone premedication (8 mg/twice daily for 3 days) or dexamethasone premedication followed by tapering dexamethasone (4 mg/daily for 2 days followed by 2 mg/daily for 2 days). The primary endpoint was absolute change in FACT-Taxane questionnaire during the first chemotherapy cycle. Secondary endpoints: proportion of patients with clinically significant TAPS, QoL, pain and toxicity.

RESULTS

110/130 patients had complete data included in the primary analysis. The fall in FACT-Taxane scores was lower in the experimental group on day 5 (p = 0.05), but not on day 7 (p = 0.21). There was no difference in FACT-Taxane scores over the entire study duration (p = 0.59). Fewer patients in the experimental arm reported TAPS on day 5 (30 vs. 47%). There was a borderline significant attenuation of impairment of QoL with experimental treatment on day 5 (p = 0.06), but not day 7 (p = 0.53). Tapered schedule was associated with more dyspepsia and insomnia.

CONCLUSION

A tapering schedule of dexamethasone was associated with a brief reduction in docetaxel-associated symptoms which was observed only during dexamethasone exposure and did not persist after discontinuation of the drug.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03348696.

A multicentre, randomised trial comparing schedules of G-CSF (filgrastim) administration for primary prophylaxis of chemotherapy-induced febrile neutropenia in early stage breast cancer

BACKGROUND

The optimal duration of filgrastim as primary febrile neutropenia (FN) prophylaxis in early breast cancer patients is unknown, with 5, 7 or 10 days being commonly prescribed. This trial evaluates whether 5 days of filgrastim was non-inferior to 7/10 days.

PATIENTS AND METHODS

In this randomised, open-label trial, early breast cancer patients who were to receive filgrastim as primary FN prophylaxis were randomly allocated to 5 versus 7 versus 10 days of filgrastim for all chemotherapy cycles. A protocol amendment in November 2017 allowed subsequent patients (N = 324) to be randomised to either 5 or 7/10 days. The primary outcome was a composite of either FN or treatment-related hospitalisations. Secondary outcomes included chemotherapy dose reductions, delays and discontinuations. Analyses were carried out by per protocol (primary) and intention-to-treat, and the non-inferiority margin was set at 3% for the risk of having FN and/or hospitalisation per cycle of chemotherapy.

RESULTS

Patients (N = 466) were randomised to receive 5 (184, 39.5%), or 7/10 (282, 60.5%) days of filgrastim. In our primary analysis, the difference in risk of either FN or treatment-related hospitalisation per cycle was -1.52% [95% confidence interval (CI): -3.22% to 0.19%] suggesting non-inferiority of a 5-day filgrastim schedule compared with 7/10-days. The difference in events per cycle for FN was 0.11% (95% CI: -1.05 to 1.27) while for treatment-related hospitalisations it was -1.68% (95% CI: -2.73% to -0.63%). The overall proportions of patients having at least one occurrence of either FN or treatment-related hospitalisation were 11.8% and 14.96% for the 5- and 7/10-day groups, respectively (risk difference: -3.17%, 95% CI: -9.51% to 3.18%).

CONCLUSION

Five days of filgrastim was non-inferior to 7/10 days. Given the cost and toxicity of this agent, 5 days should be considered standard of care. CLINICALTRIALS.

GOV REGISTRATION

NCT02428114 and NCT02816164.