Faculty Bibliography

OBJECTIVE/UNASSIGNED:This retrospective observational study described baseline characteristics, real-world treatment patterns, and outcomes among patients with metastatic breast cancer treated with abemaciclib in the United States. METHODS/UNASSIGNED:De-identified electronic health record-derived data were used to describe patients who began abemaciclib treatment on or after 30 June 2016 and ≥4 months before data cutoff (31 December 2018). Real-world response (rwR) and real-world progression assessments were abstracted from clinical documentation. Descriptive statistics were used to calculate the real-world best response. The Kaplan-Meier method estimated real-world time to first response (rwTTFR) and real-world progression-free survival (rwPFS). RESULTS/UNASSIGNED:The median age of 118 female patients at abemaciclib initiation was 66.5 years (interquartile range, 57.0, 73.0). The breakdown of patients who received abemaciclib in first, second, third, or later lines was 28.8%, 21.2%, 20.3%, and 29.7%, respectively. Patients received abemaciclib as monotherapy (12.7%) or in combination with endocrine therapy: fulvestrant (59.3%); aromatase inhibitor (22.9%); aromatase inhibitor and fulvestrant (5.1%). There were 68 patients (57.6%) with ≥1 rwR assessment: 41.2% with a real-world complete response or real-world partial response. Median rwTTFR was 3.6 months (95% confidence interval, 3.5, 5.2). Twelve-month rwPFS probability was 61.7%. CONCLUSIONS/UNASSIGNED:This study represents utilization and outcomes associated with abemaciclib approximately 1 year following FDA approval. Treatment patterns demonstrated heterogeneity and, as in clinical trials, patients appeared to benefit from abemaciclib treatment in the real world. More research investigating outcomes associated with abemaciclib treatment is needed, with larger samples and longer follow-up to enable closer evaluation by subgroup, regimen, and line of therapy.

Aim: Standard first-line treatment of advanced urothelial cell carcinoma involves cisplatin-based chemotherapy, with carboplatin or immune checkpoint inhibitor therapy (ICI) reserved for cisplatin-ineligible individuals. Methods: Using a large de-identified electronic health record-derived database of patients with advanced urothelial cell carcinoma in the USA, we examined trends in utilization of first-line systemic therapies in cisplatin-eligible patients from 1 January 2015 to 31 March 2018. Results: Among 1181 cisplatin-eligible patients, the quarterly proportion who received first-line ICI increased from 1 to 42% (p_trend <0.001), while the proportion who received cisplatin-based chemotherapy decreased from 53 to 33% (p_trend = 0.018). Patients receiving ICI were older than those receiving cisplatin (median age: 75 vs 68). Conclusion: Our analysis suggests rising off-label ICI use in cisplatin-eligible individuals, potentially because of ICI's favorable toxicity profile.

BACKGROUND:Limited data compare first-line carboplatin-based chemotherapy and immune checkpoint blockade in cisplatin-ineligible metastatic urothelial carcinoma (mUC) patients. The primary evidence guiding treatment decisions was a recent Food and Drug Administration/European Medicines Agency safety alert based on emerging data from two ongoing phase III trials, reporting shorter survival in programmed death-ligand 1 (PD-L1)-negative patients receiving immunotherapy. Final results from these trials are unknown. OBJECTIVE:To compare survival in cisplatin-ineligible mUC patients receiving first-line immunotherapy versus those receiving carboplatin-based chemotherapy. DESIGN, SETTING, AND PARTICIPANTS:We conducted a retrospective cohort study of 2017 mUC patients receiving first-line carboplatin-based chemotherapy (n = 1530) or immunotherapy (n = 487) from January 1, 2011 to May 18, 2018 using the Flatiron Health electronic health record-derived database. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS:The primary outcomes were overall survival (OS), comparing 12- and 36-mo OS, and hazard ratios before and after 12 mo. Propensity score-based inverse probability of treatment weighting (IPTW) was used to address confounding in Kaplan-Meier and Cox regression model estimates of comparative effectiveness. RESULTS AND LIMITATIONS:IPTW-adjusted OS rates in the immunotherapy group were lower at 12 mo (39.6% [95% confidence interval {CI} 34.0-45.3%] vs 46.1% [95% CI 43.4-48.8%]) but higher at 36 mo (28.3% [95% CI 21.8-34.7%] vs 13.3% [95% CI 11.1-15.5%]) relative to the chemotherapy group. Immunotherapy treatment demonstrated inferior OS during the first 12 mo relative to carboplatin-based chemotherapy (IPTW-adjusted hazard ratio [HR] 1.37, 95% CI 1.15-1.62), but superior OS beyond 12 mo (IPTW-adjusted HR 0.50, 95% CI 0.30-0.85). Limitations include retrospective design and potential unmeasured confounding. CONCLUSIONS:In the setting of mUC, clinicians and patients should carefully consider how to balance the short-term benefit of chemotherapy against the long-term benefit of immunotherapy. PATIENT SUMMARY:To determine the optimal first-line therapy for metastatic bladder cancer patients who are unfit for cisplatin, we compared carboplatin-based chemotherapy versus immunotherapy using real-world data. Survival in the 1st year of treatment was lower with immunotherapy relative to chemotherapy, but for patients surviving beyond the 1st year, immunotherapy was superior.

Several immune checkpoint inhibitor therapies (CPIs) have been approved to treat metastatic urothelial cell carcinoma (mUC). Because of the favorable toxicity profile of CPI compared with chemotherapy, oncologists may have a low threshold to prescribe CPI to patients near the end of life. We evaluated trends in initiation of end-of-life systemic therapy in 1,637 individuals in the Flatiron Health Database who were diagnosed with mUC between 2015 and 2017 and who died. Rates of systemic therapy initiation in the last 30 and 60 days of life were 17.0% and 29.8%, respectively. The quarterly proportion of patients who initiated CPI within 60 days of death increased from 1.0% to 23% during the study period (p

Sorafenib has an antitumor activity in patients with radioactive iodine-refractory differentiated thyroid carcinoma (RAIR-DTC). Prior research has implicated signaling through the MAPK and AKT/PI3K pathways in the progression of DTC. To assess whether the activity of these pathways is predictive of response to sorafenib, we retrospectively studied molecular tumor markers from these two pathways from a phase 2 study of sorafenib in RAIR-DTC. Tumor samples from 40 of 53 DTC subjects obtained prior to initiation of sorafenib were immunostained with DAB-labeled antibodies to phospho-AKT (pAKT), phospho-ERK (pERK), and phospho-S6 (pS6). BRAFV600E genetic mutation analysis was performed on all samples. Expression levels and mutational status were compared to response and progression-free survival (PFS) for each patient. Low tumor expression of nuclear pAKT was associated with partial response to sorafenib (p < 0.01). Patients with nuclear pAKT expression that was below the median for our sample were more than three times as likely to have a partial response as patients with equal to or above median expression. There was no correlation between tumor expression of nuclear pERK or pS6 and response. Endothelial cell and pericyte expression of pERK, pAKT, and pS6 were not predictive of response. There was no correlation between BRAFV600E mutation status and partial response. No correlation was observed between either the expression of pAKT, pERK, or pS6, or the presence of the BRAFV600E mutation, and PFS. In conclusion, lower tumor expression of nuclear pAKT was associated with higher rate of response to sorafenib. This observation justifies evaluation of combination therapy with sorafenib and an inhibitor of the PI3K/AKT signaling pathway in RAIR-DTC.