Expression of AR-V7 and ARv567es in Circulating Tumor Cells Correlates with Outcomes to Taxane Therapy in Men with Metastatic Prostate Cancer Treated in TAXYNERGY.

PURPOSE: Biomarkers aiding treatment optimization in metastatic castration-resistant prostate cancer (mCRPC) are scarce. The presence or absence of androgen receptor (AR) splice variants, AR-V7 and ARv567es, in mCRPC patient circulating tumor cells (CTC) may be associated with taxane treatment outcomes.Experimental Design: A novel digital droplet PCR (ddPCR) assay assessed AR-splice variant expression in CTCs from patients receiving docetaxel or cabazitaxel in TAXYNERGY (NCT01718353). Patient outcomes were examined according to AR-splice variant expression, including prostate-specific antigen (PSA)50 response and progression-free survival (PFS). RESULTS: Of the 54 evaluable patients, 36 (67%) were AR-V7+, 42 (78%) were ARv567es+, 29 (54%) were double positive, and 5 (9%) were double negative. PSA50 response rates at any time were numerically higher for AR-V7- versus AR-V7+ (78% vs. 58%; P = 0.23) and for ARv567es- versus ARv567es+ (92% vs. 57%; P = 0.04) patients. When AR-V mRNA status was correlated with change in nuclear AR from cycle 1 day 1 to day 8 (n = 24), AR-V7+ patients (n = 16) had a 0.4% decrease versus a 12.9% and 26.7% decrease in AR-V7-/ARv567es- (n = 3) and AR-V7-/ARv567es+ (n = 5) patients, respectively, suggesting a dominant role for AR-V7 over ARv567es. Median PFS was 12.02 versus 8.48 months for AR-V7- versus AR-V7+ (HR = 0.38; P = 0.01), and 12.71 versus 7.29 months for ARv567es- versus ARv567es+ (HR = 0.37; P = 0.02). For AR-V7+, AR-V7-/ARv567es+, and AR-V7-/ARv567es- patients, median PFS was 8.48, 11.17, and 16.62 months, respectively (P = 0.0013 for trend). CONCLUSIONS: Although detection of both CTC-specific AR-V7 and ARv567es by ddPCR influenced taxane outcomes, AR-V7 primarily mediated the prognostic impact. The absence of both variants was associated with the best response and PFS with taxane treatment.See related commentary by Dehm et al., p. 1696.

Real-world outcomes in patients with metastatic castration-resistant prostate cancer receiving second-line chemotherapy versus an alternative androgen receptor-targeted agent (ARTA) following early progression on a first-line ARTA in a US community oncology setting.

OBJECTIVE: This retrospective observational study assessed if second-line chemotherapy vs. androgen receptor-targeted agents (ARTAs; abiraterone/enzalutamide) is associated with improved outcomes in metastatic castration-resistant prostate cancer (mCRCaP) patients who experience early progression on first-line ARTAs in a US community setting. METHODS: Patients with mCRCaP (n = 345) who progressed ≤ 12 months after first-line ARTA and received second-line chemotherapy (docetaxel/cabazitaxel; n = 147) or ARTA (n = 198) between May 2011 and October 2014 were identified. Overall survival (OS), prostate-specific antigen (PSA) response and progression, and clinical response were compared for second-line chemotherapy vs. ARTA, using one-sided tests from second-line therapy initiation. Multivariate analyses were adjusted for: year, age, metastases, opioid use, Eastern Cooperative Oncology Group performance score, PSA, hemoglobin, alkaline phosphatase, lactate dehydrogenase (LDH), and albumin levels. RESULTS: Patients receiving second-line chemotherapy vs. ARTA were younger (median: 74 vs. 79 years) and had a poorer prognosis in terms of PSA, LDH, alkaline phosphatase, albumin and hemoglobin levels, opioid use, and Halabi risk score (P < 0.05). Response rates were higher for chemotherapy vs. ARTA (PSA: adjusted odds ratio = 2.27, P = 0.005; clinical: adjusted odds ratio = 1.78; P = 0.020) and time to PSA progression was longer (adjusted hazard ratio [aHR] = 0.66; P = 0.010). A trend favored chemotherapy vs. ARTA for OS (aHR = 0.81, P = 0.148). Among patients with poor prognostic features, those receiving chemotherapy had significantly improved OS (Halabi intermediate-/high-risk score: aHR = 0.55, P = 0.009; hemoglobin < 11 g/dl: aHR = 0.41, P = 0.002; LDH > upper limit of normal: aHR = 0.18, P = 0.014; albumin < lower limit of normal: aHR = 0.42, P = 0.020). CONCLUSION: Following early progression on first-line ARTA, second-line chemotherapy may be more beneficial in mCRCaP compared with second-line ARTA in patients with a poor prognosis.

Treatment of the chronic phase of chronic myeloid leukemia with an intermittent schedule of recombinant interferon alfa-2b and cytarabine: results from CALGB study 9013.

Despite nine studies reporting the results achieved when treating patients with chronic myeloid leukemia (CML) with interferon (rIFNalpha) and cytarabine (araC), the optimal doses and schedule for this combination remain to be determined. Results of imatinib mesylate (STI-571) in chronic phase CML are preliminary, thus, trials of rIFNalpha-2b/araC in CML are of continued interest. We report the results of CALGB study 9013, providing a 10-year follow-up on 88 evaluable previously untreated patients. Cycles of therapy with rIFNalpha-2b and araC sufficient to cause a decline in either the white blood cell (WBC) count to < 2000/microl or platelets to < 50,000/microl were given. The starting dose of rIFNalpha-2b was 5 million units (mu)/m2/day subcutaneously (s.c.) and of araC 10 mg/m2 twice daily s.c. Treatment was discontinued when cytopenia occurred and was restarted when both the WBC and platelet counts had recovered. Bone marrow was obtained regularly for morphologic, cytogenetic and molecular studies. Medians at entry included age 48 years, WBC = 89,900/microl and platelets = 345,000/microl. The performance status was 0 or 1 in 88%; splenomegaly was present in 46%. Fifty five (63%) patients had a complete hematologic response and 10 (11%) had a partial hematologic response for an overall response rate of 74%. Median time to best response was 5.3 months. Median survival for all patients from study entry was 81 months, the 5-year survival probability was 65%. When 28 patients were censored at the time of bone marrow transplantation the median survival was 82 months. Grade 3 anorexia, nausea, vomiting and diarrhea developed in 15, 27, 13 and 7%, respectively. Mild to moderate elevations of transaminases occurred in 42%, and were severe in 5%. Sixty-three patients had adequate follow-up cytogenetic studies: 10 had a complete cytogenetic response (CCyR), 23 partial (PCyR, 50-99% normal cells), 20 minor and 10 no response (CALGB criteria). Thus, the CCyR plus PCyR rate among these 63 patients was 52%. Assuming the 25 patients with no cytogenetic follow-up as non-responders, 38% of the 88 patients had at least a PCyR. The median time to CCyR or PCyR was 5.6 months. The median time to best response in these 33 patients was 10.0 months, and median duration of cytogenetic response was 28 months. Cytogenetic responders had significantly longer survival than non-responders (p = 0.01) using a landmark analysis at 18 months. This intermittent schedule of rIFNalpha-2b/ara-C has a high response rate in patients with CML with acceptable toxicity.

Lineage specific treatment of adult patients with acute lymphoblastic leukemia in first remission with anti-B4-blocked ricin or high-dose cytarabine: Cancer and Leukemia Group B Study 9311.

BACKGROUND: Anti-B4-blocked ricin is an immunotoxin comprised of an anti-CD19 murine monoclonal antibody (B4) conjugated to blocked ricin, which has cytotoxic activity in patients with lymphoid malignancies. METHODS: Adults with untreated acute lymphoblastic leukemia (ALL) were treated with a previously developed and tested chemotherapeutic regimen. Patients with CD19 positive ALL were given anti-B4-blocked ricin as 2 7-day continuous infusions 1 week apart. Patients with CD19 negative ALL received high-dose cytarabine. Serial polymerase chain reaction (PCR) assays of BCR-ABL, immunoglobulin heavy chain (IGH), and T-cell receptor (TCR) genes were used to measure the impact of lineage specific intensification treatment on minimal residual disease. RESULTS: Eighty-two adults were enrolled, and 78 were eligible. The median age was 34 years (range, 17-81 years). Sixty-six patients (85%) achieved complete remission. Forty-six patients received the anti-B4-blocked ricin, which generally was well tolerated; 80% were able to receive both courses. The most common toxicity was asymptomatic transient elevation of liver function tests in 72% of patients. Lymphopenia occurred in 46% of patients. Two patients developed antibodies to the anti-B4-blocked ricin. Molecular monitoring before and after the experimental course of intensification did not show a consistent change in the number of leukemia cells remaining, and the immediate posttreatment PCR studies did not correlate with remission duration. CONCLUSIONS: Intensification therapy with anti-B4-blocked ricin is feasible for patients with CD19 positive ALL, although there is little evidence of an additional clinical benefit from the anti-B4-blocked ricin. Cancer 2003;97:1471-80.

Phase II study of oral capecitabine in patients with advanced or metastatic pancreatic cancer.

PURPOSE: To determine the safety and efficacy of capecitabine (Xeloda; Roche Laboratories, Nutley, NJ) in patients with metastatic or unresectable, locally advanced pancreatic cancer. PATIENTS AND METHODS: Forty-two patients were treated with oral capecitabine 1,250 mg/m(2) administered twice daily (2,500 mg/m(2)/d) as intermittent therapy in 3-week cycles consisting of 2 weeks of treatment followed by 1 week without treatment. Tumor lesions were assessed by computed tomography scan or physical examination at 6-week intervals (after every two cycles). Adverse events were monitored continuously during treatment and for 28 days after the last dose of study drug. RESULTS: Ten (24%) of 42 patients experienced a clinical benefit response (95% confidence interval [CI], 12.1% to 39.5%) as evidenced by improvement in pain intensity, analgesic consumption, and/or Karnofsky performance status. Three (7.3%) of the 41 patients with measurable disease had an objective response (partial). The median time to objective response was 85 days (range, 47 to 91 days) and duration of response was 208, 260, and 566 days for the three responding patients. One patient with nonmeasurable but assessable disease had improved residual disease with a positive clinical benefit response, for a total of four responses among the 42 assessable patients, for an overall response rate of 9.5% (90% CI, 3.3% to 20.5%). Capecitabine was generally well tolerated. CONCLUSION: Treatment with capecitabine resulted in clinically significant beneficial effects on tumor-related symptoms and yielded objective response activity in patients with metastatic or locally advanced pancreatic cancer. These results together with its generally tolerable safety profile and the added advantage of oral administration provide the basis for further evaluating capecitabine as a single agent or in combination with other treatment modalities in this patient population.