Efficacy of antiandrogens in androgen receptor-positive triple-negative metastatic breast cancer: Real-life data

Antiandrogens (AA) have been tested in clinical trials in androgen receptor (AR) + triple-negative breast cancer (TNBC). We aim to assess the clinical benefit rate (CBR) of AA in real life. The primary end-point was CBR at 6 months. Twenty-four patients were assessable and received: abiraterone acetate (62 %), enzalutamide (8 %) and bicalutamide (30 %). CBR at 6 months was 29 % (7/24) with 2 CR, 3 PR and 2 SD. Four patients had a clinical benefit >12 months. Real-life efficacy of AA use in metastatic AR + TNBC are in line with data from published trials.

Phase II study of metronomic treatment with daily oral vinorelbine as first-line chemotherapy in patients with advanced/metastatic HR+/HER2- breast cancer resistant to endocrine therapy: VinoMetro-AGO-B-046

Purpose

Metronomic chemotherapy (MCT) is an increasingly used treatment option in hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2−) advanced/metastatic breast cancer (MBC) after failure of endocrine-based therapies.

Methods

VinoMetro was a multicentre, open-label, single-arm, phase II study of metronomic oral vinorelbine (VRL; 30 mg/day) as a first-line chemotherapy (CT) in patients with HR+/HER2− MBC after endocrine failure. The primary endpoint was the clinical benefit rate (CBR) at 24 weeks.

Results

Between January 2017 and April 2019, nine patients were enrolled. The CBR was 22.2% (90% confidence interval [CI] 4.1–55.0), p = 0.211. The median progression-free survival (PFS) was 12.0 weeks (95% CI 11.3–12.7). Grade 3–4 adverse events (AEs) occurred in 22.2% of patients. One patient died of febrile neutropenia.

Conclusion

VinoMetro (AGO-B-046) was closed early after nine patients and occurrence of one grade 5 toxicity in agreement with the lead institutional review board (IRB). Metronomic dosing of oral VRL in HR+/HER2− MBC as first-line CT after failure of endocrine therapies showed only limited benefit in this population.

Trial registration number and date of registration

ClinicalTrials.gov Identifier: NCT03007992; December 15, 2016.

Efficacy and safety of selective cyclin-dependent kinases 4/6 inhibitors in hormone-receptor-positive, HER2-negative advanced breast cancer - results from a real-world setting

BACKGROUND

Selective cyclin-dependent kinases 4/6 inhibitors (CDKi) have become the standard of care in patients with hormone receptor (HR)-positive, HER2-negative advanced breast cancer (ABC). We performed retrospective analysis in patients treated with CDKi in the first year of their routine clinical use in Slovenia.

METHODS

The primary goals were time-to-treatment failure (TTF) and overall survival (OS), analysed via Kaplan-Meier method, the secondary goals were clinical benefit rate (CBR) and safety.

RESULTS

Overall, 218 patients' data were evaluated. The median age was 61.8 years (30.6-84.6). The median number of previous ET lines for ABC was 2 (range 0-5). At the time of inclusion, 128 patients (58.7%) had visceral metastases, 45 patients (20.6%) had bone-only disease. At the median follow-up of 15.2 months, disease progressed in 74 patients and 60 patients died. The median TTF was 8.3 months for the whole group, 19.3, 10.3 and 5.5 months for patients treated in the first-, second- and further lines of systemic therapy, respectively. The median OS from the start of CDKi treatment was not reached in any of the groups. CBR was 59.6% for the whole group, 42.7% for further lines of therapy. The most common grade 3/4 adverse event was neutropaenia in 108 patients (49.5%), followed by an increase of hepatic aminotransferases in 13 patients (6.0%).

CONCLUSIONS

Even in the diverse real-world population treatment with CDKi in combination with ET showed clinical benefit, most prominently in the first- and second lines of systemic therapy.

A phase II study of pazopanib as front-line therapy in patients with non-resectable or metastatic soft-tissue sarcomas who are not candidates for chemotherapy

BACKGROUND

Cytotoxic chemotherapy remains the standard of care first-line treatment for advanced and metastatic soft-tissue sarcomas (STSs). Certain patients may not be chemotherapy candidates based upon age or co-morbidities, leaving limited treatment options. Pazopanib is a multi-targeted tyrosine kinase inhibitor that is FDA-approved for metastatic STS after the first line. We proposed a phase II study evaluating pazopanib as a first-line agent in patients with advanced disease who are deemed not to be candidates for chemotherapy.

METHODS

Eligible patients were at least 18 years old, not candidates for chemotherapyand were treatment naive. Pazopanib was titrated from 200 mg twice daily to a goal of 800 mg daily. The primary end point was the clinical benefit rate (CBR) (CBR = completed response + partial response + stable disease per Response Evaluation Criteria in Solid Tumours [RECIST 1.1]) at 16 weeks. The sample size of 56 evaluable patients was calculated to provide 80% power to test a hypothesised CBR of ≥35% against an unfavourable CBR of ≤20%. If ≥ 17 patients achieved benefit, the null CBR of 20% would be rejected at a nominal 5% alpha level. Secondary end points included progression-free survival (PFS), overall survival (OS), quality of life and serum biomarkers.

FINDINGS

Fifty-six patients were enrolled from May 2015 to February 2019 and are included in the intention-to-treat analysis. Median PFS was 3.67 (2.62-7.25) months. Median OS was 14.16 (95% confidence interval [CI]: 8.4-NR) months, CBR = 39.29% (22/56) (CI = 0.265-0.533, p = 0.0007). No new or unexpected adverse events were seen. The most common grade I-II events were diarrhoea, nausea and fatigue. The most common grade III-IV events were hypertension and liver function test abnormalities.

INTERPRETATION

These data suggest that there is a benefit to front-line pazopanib in patients with STS who are not candidates for cytotoxic chemotherapy.

alternative endocrine therapies for hormone receptor-positive advanced breast cancer

BACKGROUND

Fulvestrant, a selective estrogen receptor degrader, is approved for first- and second-line treatment of postmenopausal women with hormone receptor-positive advanced breast cancer (ABC).

METHODS

Meta-analysis of randomized controlled trials (RCTs) evaluating fulvestrant 500 mg in postmenopausal hormone receptor-positive ABC, to evaluate differences in clinical benefit rate (CBR; proportion of patients experiencing best overall response of complete response, partial response, or stable disease for ≥ 24 weeks) between fulvestrant 500 mg and comparator endocrine therapies. Odds ratios (OR) and 95% confidence intervals (CI) for CBR were calculated; fixed effects (FE) models were constructed (first- and second-line data, alone and combined).

RESULTS

Six RCTs were included. Four studies evaluated fulvestrant 500 mg vs. fulvestrant 250 mg; two evaluated fulvestrant 500 mg vs. anastrozole 1 mg. In total, 1054 and 534 patients were included (first- and second-line treatment, respectively). Analysis of OR and 95% CI of CBR by therapy line favored fulvestrant 500 mg vs. comparator therapy. Assessing all results combined in the FE model indicated significant improvement in CBR with fulvestrant 500 mg vs. comparator treatments (OR 1.33; 95% CI 1.13-1.57; p = 0.001). Restricting the FE model to therapy line demonstrated significant improvement in CBR vs. comparator treatments (OR 1.33; 95% CI 1.02-1.73; p = 0.035) for first-line, and a trend to improvement vs. comparator treatments (OR 1.27; 95% CI 0.90-1.79; p = 0.174) for second-line.

CONCLUSIONS

In postmenopausal patients with hormone receptor-positive ABC, fulvestrant 500 mg first-line was associated with significantly greater CBR (more patients benefiting from treatment) vs. comparator endocrine therapy.