Patient-reported outcomes for patients with metastatic castration-resistant prostate cancer receiving docetaxel and Atrasentan versus docetaxel and placebo in a randomized phase III clinical trial (SWOG S0421)

Background

SWOG S0421 was a large randomized trial comparing docetaxel/prednisone plus placebo (DPP) to docetaxel/prednisone plus atrasentan over 12 cycles for patients with metastatic castration-resistant prostate cancer (mCRPC). The current report presents the PRO results for this trial, an important secondary endpoint.

Methods

The trial specified two primary PRO endpoints. Palliation of worst pain was based on the Brief Pain Inventory (BPI), where a 2 point difference is defined as clinically meaningful. Improvement of functional status was based on the Functional Assessment of Cancer Therapy – Prostate Cancer Trial Outcome Index (FACT-P TOI); a 5-point difference has been defined as clinically meaningful. We compared rates by arm using chi-square tests. Longitudinal analyses using linear mixed models addressed changes by arm over time.

Results

Four-hundred eighty-nine patients on each arm were evaluable for PRO endpoint data. There were no differences by arm in clinically meaningful pain palliation (41.7% for DPP vs. 44.0% for DPA, p = .70) or functional status (24.2% for DPP vs. 28.7% for DPA, p = .13). Longitudinal comparisons indicated no differences over time by arm for BPI Worst Pain scores (0.13 points, p = .23). Patients on the DPA arm had improved functional status of 1.78 points on average, a statistically significant (p = .02) but not clinically meaningful difference.

Conclusions

The SWOG S0421 PRO data showed little evidence of clinically meaningful differences by arm in either pain palliation or functional status.

Electronic supplementary material

The online version of this article (10.1186/s41687-018-0054-5) contains supplementary material, which is available to authorized users.

Costimulatory molecule profiles and NK cell recovery after autologous hematopoietic cell transplantation (HCT) in multiple myeloma (MM) patients

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Background: Increased immune responses post autologous HCT may be of benefit in long term disease control. Responses may be mediated by NK cell function and possibly other alternate pathways, including costimulatory molecule pathways. This pilot study assesses the expression of inhibitory (PD-1 and CTLA-4) and stimulatory (OX-40, ICOS, 4-1BB, and CD28) molecules on NK cells after auto-HCT in MM patients and evaluates the effect of lenalidomide treatment on these pathways. Methods: 17 patients with MM undergoing HCT, median age 56.7 years (36 – 67), were included in the study. Peripheral blood samples were taken 3 days prior to HCT and 14, 30, 60, 90, 180 days after HCT. At d180 post-HCT, 13/17 patients were receiving lenalidomide with d91 as median start date. NK cells and their costimulatory molecules were evaluated by flowcytometry using 2 six color panels of antibodies. One way ANOVA test and Kruskal-Wallis test (non-parametric) were applied to analyze the data using the Graphpad Software. Results: See table below. NK cell number was highest (median: 26% of total lymphocytes) at d14 (p: < 0.0001) compared to pre and post HCT levels. At d180, TNF-R OX40 expression was significantly increased in ≤PR group (n=5) (median: 9.5% of NK cells) compared to ≥VGPR (n=12) (0.8%; p=0.0084). In addition, NK cell number was higher in the lenalidomide group (n=13) (median: 15.15 % of total lymphocytes) compared to the no lenalidomide group (n=4) (6.74%; p=0.0108) at d180 post HCT. Significantly lower level of CTLA-4 expression was also found in the lenalidomide group (0.33% vs. 2.54%; p=0.0362). Conclusions: We observed NK cell recovery to baseline values at 60 days after HCT. At d180 post-HCT, OX-40 expression in NK cells was higher in ≤PR group than ≥VGPR group. Lenalidomide treatment was associated with higher NK cells number and decreased expression of CTLA-4. This observation could be a possible marker of enhanced host NK cell immune response against MM. Future clinical trials will explore therapies that increase NK cell responses. [Table: see text]

Sequential bortezomib, dexamethasone, and thalidomide maintenance therapy after single autologous peripheral stem cell transplantation in patients with multiple myeloma

We report feasibility and response results of a phase II study investigating prolonged weekly bortezomib and dexamethasone followed by thalidomide and dexamethasone as maintenance therapy after single autologous stem cell transplantation (ASCT) in patients with multiple myeloma. Within 4 to 8 weeks of ASCT, patients received weekly bortezomib and dexamethasone for six cycles, followed by thalidomide and dexamethasone for six more cycles. Thalidomide alone was continued until disease progression. Forty-five patients underwent ASCT. Forty patients started maintenance therapy; of these, 36 patients received four cycles, and 32 completed six cycles of maintenance bortezomib. Of these 40 patients, nine (22%) were in complete response (CR) before ASCT, 13 (32%) achieved CR after ASCT but before bortezomib maintenance therapy, and 21 (53%) achieved CR after bortezomib maintenance therapy. Nine patients not previously in CR (33%) upgraded their response to CR with bortezomib maintenance. At 1 year post-ASCT, 20 patients achieved CR, and two achieved very good partial response. Twenty-seven patients experienced peripheral neuropathy during bortezomib therapy, all grade 1 or 2. Our findings indicate that prolonged sequential weekly bortezomib, dexamethasone, and thalidomide maintenance therapy after single ASCT is feasible and well tolerated. Bortezomib maintenance treatment upgraded post-ASCT CR responses with no severe grade 3/4 peripheral neuropathy.