Safety Analyses of the Phase 3 VISION Trial of [177Lu]Lu-PSMA-617 in Patients with Metastatic Castration-resistant Prostate Cancer.

BACKGROUND AND OBJECTIVE: [177Lu]Lu-PSMA-617 (177Lu-PSMA-617) plus the standard of care (SoC) significantly improved overall survival and radiographic progression-free survival versus SoC alone in patients with prostate-specific membrane antigen (PSMA)-positive metastatic castration-resistant prostate cancer in the VISION trial. We evaluated the safety of additional cycles of 177Lu-PSMA-617 and the impact of longer observation time for patients receiving 177Lu-PSMA-617 plus SoC. METHODS: VISION was an international, open-label study. Patients were randomised 2:1 to receive 177Lu-PSMA-617 plus SoC or SoC alone. The incidence of treatment-emergent adverse events (TEAEs) was assessed in prespecified subgroups of patients who received ≤4 cycles versus 5-6 cycles of treatment and during each cycle of treatment. The TEAE incidence was also adjusted for treatment exposure to calculate the incidence per 100 patient-treatment years of observation. This analysis was performed for the first occurrence of TEAEs. KEY FINDINGS AND LIMITATIONS: The any-grade TEAE incidence was similar in cycles 1-4 and cycles 5-6. TEAE frequency was similar across all cycles of 177Lu-PSMA-617 treatment. No additional safety concerns were reported for patients who received >4 cycles. The exposure-adjusted safety analysis revealed that the overall TEAE incidence was similar between arms, but distinct trends for different TEAE types were noted and the incidence of events associated with 177Lu-PSMA-617 remained higher in the 177Lu-PSMA-617 arm. CONCLUSIONS AND CLINICAL IMPLICATIONS: Longer exposure to 177Lu-PSMA-617 plus SoC was not associated with a higher toxicity risk, and the extended time for safety observation could account for the higher TEAE incidence in comparison to SoC alone. The findings support a favourable benefit-risk profile for 6 cycles of 177Lu-PSMA-617 in this setting and the use of up to 6 cycles of 177Lu-PSMA-617 in patients who are clinically benefiting from and tolerating this therapy. PATIENT SUMMARY: For patients with metastatic prostate cancer no longer responding to hormone therapy, an increase in the number of cycles of treatment with a radioactive compound called 177Lu-PSMA-617 from four to six had no additional adverse side effects.

Health-related quality of life and pain outcomes with [177Lu]Lu-PSMA-617 plus standard of care versus standard of care in patients with metastatic castration-resistant prostate cancer (VISION): a multicentre, open-label, randomised, phase 3 trial.

BACKGROUND: In VISION, the prostate-specific membrane antigen (PSMA)-targeted radioligand therapy lutetium-177 [177Lu]Lu-PSMA-617 (vipivotide tetraxetan) improved radiographic progression-free survival and overall survival when added to protocol-permitted standard of care in patients with metastatic castration-resistant prostate cancer. Here, we report additional health-related quality of life (HRQOL), pain, and symptomatic skeletal event results. METHODS: This multicentre, open-label, randomised, phase 3 trial was conducted at 84 cancer centres in nine countries in North America and Europe. Eligible patients were aged 18 years or older; had progressive PSMA-positive metastatic castration-resistant prostate cancer; an Eastern Cooperative Oncology Group (ECOG) performance status score of 0-2; and had previously received of at least one androgen receptor pathway inhibitor and one or two taxane-containing regimens. Patients were randomly assigned (2:1) to receive either [177Lu]Lu-PSMA-617 plus protocol-permitted standard of care ([177Lu]Lu-PSMA-617 group) or standard of care alone (control group) using permuted blocks. Randomisation was stratified by baseline lactate dehydrogenase concentration, liver metastases, ECOG performance status, and androgen receptor pathway inhibitor inclusion in standard of care. Patients in the [177Lu]Lu-PSMA-617 group received intravenous infusions of 7·4 gigabecquerel (GBq; 200 millicurie [mCi]) [177Lu]Lu-PSMA-617 every 6 weeks for four cycles plus two optional additional cycles. Standard of care included approved hormonal treatments, bisphosphonates, and radiotherapy. The alternate primary endpoints were radiographic progression-free survival and overall survival, which have been reported. Here we report the key secondary endpoint of time to first symptomatic skeletal event, and other secondary endpoints of HRQOL assessed with the Functional Assessment of Cancer Therapy-Prostate (FACT-P) and EQ-5D-5L, and pain assessed with the Brief Pain Inventory-Short Form (BPI-SF). Patient-reported outcomes and symptomatic skeletal events were analysed in all patients who were randomly assigned after implementation of measures designed to reduce the dropout rate in the control group (on or after March 5, 2019), and safety was analysed according to treatment received in all patients who received at least one dose of treatment. This trial is registered with ClinicalTrials.gov, NCT03511664, and is active but not recruiting. FINDINGS: Between June 4, 2018, and Oct 23, 2019, 831 patients were enrolled, of whom 581 were randomly assigned to the [177Lu]Lu-PSMA-617 group (n=385) or control group (n=196) on or after March 5, 2019, and were included in analyses of HRQOL, pain, and time to first symptomatic skeletal event. The median age of patients was 71 years (IQR 65-75) in the [177Lu]Lu-PSMA-617 group and 72·0 years (66-76) in the control group. Median time to first symptomatic skeletal event or death was 11·5 months (95% CI 10·3-13·2) in the [177Lu]Lu-PSMA-617 group and 6·8 months (5·2-8·5) in the control group (hazard ratio [HR] 0·50, 95% CI 0·40-0·62). Time to worsening was delayed in the [177Lu]Lu-PSMA-617 group versus the control group for FACT-P score (HR 0·54, 0·45-0·66) and subdomains, BPI-SF pain intensity score (0·52, 0·42-0·63), and EQ-5D-5L utility score (0·65, 0·54-0·78). Grade 3 or 4 haematological adverse events included decreased haemoglobin (80 [15%] of 529 assessable patients who received [177Lu]Lu-PSMA-617 plus standard of care vs 13 [6%] of 205 who received standard of care only), lymphocyte concentrations (269 [51%] vs 39 [19%]), and platelet counts (49 [9%] vs five [2%]). Treatment-related adverse events leading to death occurred in five (1%) patients who received [177Lu]Lu-PSMA-617 plus standard of care (pancytopenia [n=2], bone marrow failure [n=1], subdural haematoma [n=1], and intracranial haemorrhage [n=1]) and no patients who received standard of care only. INTERPRETATION: [177Lu]Lu-PSMA-617 plus standard of care delayed time to worsening in HRQOL and time to skeletal events compared with standard of care alone. These findings support the use of [177Lu]Lu-PSMA-617 in patients with metastatic castration-resistant prostate cancer who received previous androgen receptor pathway inhibitor and taxane treatment. FUNDING: Advanced Accelerator Applications (Novartis).

Lutetium-177-PSMA-617 for Metastatic Castration-Resistant Prostate Cancer.

BACKGROUND: Metastatic castration-resistant prostate cancer remains fatal despite recent advances. Prostate-specific membrane antigen (PSMA) is highly expressed in metastatic castration-resistant prostate cancer. Lutetium-177 (177Lu)-PSMA-617 is a radioligand therapy that delivers beta-particle radiation to PSMA-expressing cells and the surrounding microenvironment. METHODS: We conducted an international, open-label, phase 3 trial evaluating 177Lu-PSMA-617 in patients who had metastatic castration-resistant prostate cancer previously treated with at least one androgen-receptor-pathway inhibitor and one or two taxane regimens and who had PSMA-positive gallium-68 (68Ga)-labeled PSMA-11 positron-emission tomographic-computed tomographic scans. Patients were randomly assigned in a 2:1 ratio to receive either 177Lu-PSMA-617 (7.4 GBq every 6 weeks for four to six cycles) plus protocol-permitted standard care or standard care alone. Protocol-permitted standard care excluded chemotherapy, immunotherapy, radium-223 (223Ra), and investigational drugs. The alternate primary end points were imaging-based progression-free survival and overall survival, which were powered for hazard ratios of 0.67 and 0.73, respectively. Key secondary end points were objective response, disease control, and time to symptomatic skeletal events. Adverse events during treatment were those occurring no more than 30 days after the last dose and before subsequent anticancer treatment. RESULTS: From June 2018 to mid-October 2019, a total of 831 of 1179 screened patients underwent randomization. The baseline characteristics of the patients were balanced between the groups. The median follow-up was 20.9 months. 177Lu-PSMA-617 plus standard care significantly prolonged, as compared with standard care, both imaging-based progression-free survival (median, 8.7 vs. 3.4 months; hazard ratio for progression or death, 0.40; 99.2% confidence interval [CI], 0.29 to 0.57; P<0.001) and overall survival (median, 15.3 vs. 11.3 months; hazard ratio for death, 0.62; 95% CI, 0.52 to 0.74; P<0.001). All the key secondary end points significantly favored 177Lu-PSMA-617. The incidence of adverse events of grade 3 or above was higher with 177Lu-PSMA-617 than without (52.7% vs. 38.0%), but quality of life was not adversely affected. CONCLUSIONS: Radioligand therapy with 177Lu-PSMA-617 prolonged imaging-based progression-free survival and overall survival when added to standard care in patients with advanced PSMA-positive metastatic castration-resistant prostate cancer. (Funded by Endocyte, a Novartis company; VISION ClinicalTrials.gov number, NCT03511664.).

Phase IB Dose Escalation and Expansion Study of AKT Inhibitor Afuresertib with Carboplatin and Paclitaxel in Recurrent Platinum-resistant Ovarian Cancer.

PURPOSE: Preclinically, AKT kinase inhibition restores drug sensitivity in platinum-resistant tumors. Here the pan-AKT kinase inhibitor afuresertib was given in combination with paclitaxel and carboplatin (PC) in patients with recurrent platinum-resistant epithelial ovarian cancer (PROC) and primary platinum-refractory ovarian cancer (PPROC). PATIENTS AND METHODS: Part I was a combination 3+3 dose escalation study for recurrent ovarian cancer. Patients received daily continuous oral afuresertib at 50-150 mg/day with intravenous paclitaxel (175 mg/m2) and carboplatin (AUC5) every 3 weeks for six cycles followed by maintenance afuresertib at 125 mg/day until progression or toxicity. Part II was a single-arm evaluation of the clinical activity of this combination in recurrent PROC (Cohort A) or PPROC (Cohort B). Patients received oral afuresertib at the MTD defined in Part I in combination with PC for six cycles, followed by maintenance afuresertib. Primary endpoints were safety and tolerability of afuresertib in combination with PC (Part I, dose escalation), and investigator-assessed overall response rate (ORR) as per RECIST version 1.1 (Part II). RESULTS: Twenty-nine patients enrolled into Part I, and 30 into Part II. Three dose-limiting toxicities of grade 3 rash were observed, one at 125 mg and two at 150 mg afuresertib. The MTD of afuresertib in combination with PC was therefore identified as 125 mg/day. The most common (≥50%) drug-related adverse events observed in Part I of the study were nausea, diarrhea, vomiting, alopecia, fatigue, and neutropenia and, in Part II, were diarrhea, fatigue, nausea, and alopecia. The Part II ORR in the intention to treat patients was 32% [95% confidence interval (CI), 15.9-52.4] by RECIST 1.1 and 52% (95% CI, 31.3-72.2) by GCIG CA125 criteria. Median progression-free survival was 7.1 months (95% CI, 6.3-9.0 months). CONCLUSIONS: Afuresertib plus PC demonstrated efficacy in recurrent PROC with the MTD of afuresertib defined as 125 mg/day.

Final overall survival analysis of a phase II trial evaluating vinorelbine and lapatinib in women with ErbB2 overexpressing metastatic breast cancer.

Lapatinib plus capecitabine (lap+cap) is approved as treatment for patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC), who have progressed on prior trastuzumab in the metastatic setting. We previously reported progression-free survival (PFS), overall survival (OS) and safety results from this open-label, multicentre, phase II study (VITAL; NCT01013740) conducted in women with HER2 positive MBC, to evaluate the efficacy and safety of lap plus vinorelbine (lap+vin), an important chemotherapy option for MBC, compared with lap+cap. In total, 112 patients were randomised 2:1 to treatment with lap+vin (N = 75) or lap+cap (N = 37). Results showed that the median PFS (primary endpoint) and OS (secondary endpoint) post-randomisation were comparable between treatment arms, with no new safety signals detected. Here, we assessed the final OS in this study at 40 months post-randomisation. At the time of final analyses, 24 (32%) patients were ongoing in the lap+vin arm, compared with 14 (38%) patients in the lap+cap arm (92% in both arms had discontinued treatment). Median OS in the lap+vin arm was 23.3 months (95% confidence intervals [CI]: 18.5, 31.1), compared with 20.3 months (95% CI: 16.4, 31.8) in the lap+cap arm. The median follow-up in the lap+vin arm was 18.86 months (95% CI: 10.68, 26.02), compared with 19.38 (95% CI: 25.56) months in the lap+cap arm. Similar rates of death (56-57%) were observed in both arms. The final OS was consistent with the previously reported data and suggest that lap+vin offers an effective treatment option for women with HER2-positive MBC.

CEREBEL (EGF111438): A Phase III, Randomized, Open-Label Study of Lapatinib Plus Capecitabine Versus Trastuzumab Plus Capecitabine in Patients With Human Epidermal Growth Factor Receptor 2-Positive Metastatic Breast Cancer.

PURPOSE: CEREBEL compared the incidence of CNS metastases as first site of relapse in patients with human epidermal growth factor receptor 2-positive metastatic breast cancer receiving lapatinib-capecitabine or trastuzumab-capecitabine. PATIENTS AND METHODS: Patients without baseline CNS metastases were randomly assigned (1:1) to receive lapatinib-capecitabine (lapatinib 1,250 mg per day; capecitabine 2,000 mg/m(2) per day on days 1 to 14 every 21 days) or trastuzumab-capecitabine (trastuzumab loading dose of 8 mg/kg followed by an infusion of 6 mg/kg every 3 weeks; capecitabine 2,500 mg/m(2) per day on days 1 to 14 every 21 days). The primary end point was incidence of CNS metastases as first site of relapse. Secondary end points included progression-free survival (PFS) and overall survival (OS). RESULTS: The study was terminated early with 540 enrolled patients (271 received lapatinib-capecitabine, and 269 received trastuzumab-capecitabine). Incidence of CNS metastases as first site of relapse was 3% (eight of 251 patients) for lapatinib-capecitabine and 5% (12 of 250 patients) for trastuzumab-capecitabine (treatment differences, -1.6%; 95% CI, -2% to 5%; P = .360). PFS and OS were longer with trastuzumab-capecitabine versus lapatinib-capecitabine (hazard ratio [HR] for PFS, 1.30; 95% CI, 1.04 to 1.64; HR for OS, 1.34; 95% CI, 0.95 to 1.64). Serious adverse events were reported in 13% (34 of 269 patients) and 17% (45 of 267 patients) of patients in the lapatinib-capecitabine and trastuzumab-capecitabine arms, respectively. CONCLUSION: CEREBEL is inconclusive for the primary end point, and no difference was detected between lapatinb-capecitabine and trastuzumab-capecitabine for the incidence of CNS metastases. A better outcome was observed with trastuzumab-capecitabine in the overall population. However, lapatinib-capecitabine efficacy may have been affected by previous exposure to a trastuzumab regimen and/or when treatment was given as first- or second-line therapy in the metastatic setting.

Association of phosphatase and tensin homolog low and phosphatidylinositol 3-kinase catalytic subunit alpha gene mutations on outcome in human epidermal growth factor receptor 2-positive metastatic breast cancer patients treated with first-line lapatinib plus paclitaxel or paclitaxel alone.

INTRODUCTION: Phosphatidylinositol 3-kinase (PI3K) pathway deregulation (that is PIK3CA mutations and/or phosphatase and tensin homolog (PTEN) loss) has been shown to enhance breast cancer cell survival and confer resistance to chemotherapeutic agents. We studied the prognostic and predictive value of PIK3CA mutations and PTEN low in patients receiving paclitaxel alone or in combination with lapatinib. METHODS: Immunohistochemistry and mutation analyses were used to evaluate PTEN and PIK3CA, respectively. Kaplan-Meier analysis with log-rank tests, logistic regression and Cox models were used in analyses of these biomarkers with efficacy endpoints. RESULTS: In the overall population, PIK3CA mutations were associated with poorer overall survival (OS) (hazard ratio (HR) = 1.87; 95% confidence interval (CI): 1.22, 2.88; P = 0.001). PTEN expression was not associated with OS (P = 0.474). In the PIK3CA wild-type subgroup, lapatinib plus paclitaxel reduced risk of progression compared with paclitaxel alone (HR = 0.44; 95% CI: 0.28, 0.69; P <0.0001); progression-free survival (PFS) was not significantly improved within the PIK3CA mutation subgroup (P = 0.179). In the PTEN low group, OS was improved with addition of lapatinib (P = 0.039). In both PTEN subgroups, addition of lapatinib was associated with improvements in PFS (P <0.050). PIK3CA and PTEN were not predictive of treatment based on interaction tests (P >0.05). CONCLUSIONS: PTEN was neither a significant prognostic nor predictive factor. PIK3CA mutations were an adverse prognostic factor for survival but not predictive for lapatinib benefit. TRIAL REGISTRATION: ClinicalTrials.gov NCT00281658 (registered 23 January 2006).

A phase II, randomized, multicenter study evaluating the combination of lapatinib and vinorelbine in women with ErbB2 overexpressing metastatic breast cancer.

Lapatinib is approved in combination with capecitabine for treatment of patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) who have progressed on prior trastuzumab in the metastatic setting. Vinorelbine is an important chemotherapy option for MBC. We evaluated efficacy and safety of lapatinib plus vinorelbine, compared with lapatinib plus capecitabine, in women with HER2-positive MBC. In this open-label, multicenter, phase II study, eligible patients (N = 112) were randomized 2:1 to lapatinib plus vinorelbine [(N = 75) 1,250 mg orally once daily (QD) continuously plus 20 mg/m(2)/day intravenously] or lapatinib plus capecitabine [(N = 37) 1,250 mg orally QD continuously plus 2,000 mg/m(2)/day orally, 2 doses]. The primary endpoint was progression-free survival (PFS). Other endpoints included overall survival (OS) and safety. Patients progressing within the study were given the option of crossover to the other treatment arm; time to second progression was an exploratory endpoint. Patient demographics, stratification, and prognostic factors were well balanced between treatments. Median PFS in both arms was 6.2 months [95 % confidence interval (CI) 4.2, 8.8 (lapatinib plus vinorelbine); 4.4, 8.3 (lapatinib plus capecitabine)]. Median OS on lapatinib plus vinorelbine was 24.3 months (95 % CI 16.4, NE) and 19.4 months (95 % CI 16.4, 27.2) on lapatinib plus capecitabine. In total, 42 patients opted to cross over; median PFS was 3.2 months (95 % CI 1.7, 5.1) on lapatinib plus vinorelbine and 4.0 months (95 % CI 2.1, 5.8) on lapatinib plus capecitabine. Lapatinib plus vinorelbine offers an effective treatment option for patients with HER2-overexpressing MBC, having displayed comparable efficacy and tolerability rates to lapatinib plus capecitabine.

Phase II study of lapatinib in combination with vinorelbine, as first or second-line therapy in women with HER2 overexpressing metastatic breast cancer.

BACKGROUND: Lapatinib in combination with capecitabine is approved for the treatment of patients with advanced or metastatic breast cancer whose tumors overexpress the human epidermal growth factor receptor 2 (HER2) and who have received prior therapy including an anthracycline, a taxane, and trastuzumab. Based on our phase I trial, we conducted a single arm, multicenter phase II study of lapatinib in combination with vinorelbine. PATIENT AND METHODS: Women with HER2-positive advanced breast cancer, who had received up to one prior regimen for metastatic disease, were eligible. Prior trastuzumab was allowed. Patients received daily lapatinib 1500 mg orally and vinorelbine 20 mg/m(2) intravenously on days 1, 8 and 15 of a 28-day cycle. The primary endpoint was overall response rate (ORR). RESULTS: Forty-four patients received the combination treatment, including 48% as second-line therapy. The ORR was 41% (95% confidence interval [CI] 26-55%), including 9% with a complete response. Median progression-free survival was 24.1 weeks (95% CI 17-37 weeks) and median duration of response was 32 weeks (95% CI 18-42 weeks). Nearly 80% of patients did not require a dose reduction in lapatinib, although most patients required one dose reduction of vinorelbine secondary to neutropenia. The most common toxicities were grade 1 and 2 diarrhea, nausea, fatigue and rash, and grade 3 and 4 neutropenia. One case of grade 3 asymptomatic decreased left ventricular ejection fraction event was reported. CONCLUSION: The combination of lapatinib and vinorelbine was active, feasible and well tolerated in patients with HER2-positive advanced breast cancer.

Randomized trial of lapatinib versus placebo added to paclitaxel in the treatment of human epidermal growth factor receptor 2-overexpressing metastatic breast cancer.

PURPOSE: Lapatinib is an oral small-molecule tyrosine kinase inhibitor of both epidermal growth factor receptor and human epidermal growth factor receptor 2 (HER2). This study is designed to test whether the addition of lapatinib to paclitaxel improves overall survival (OS) compared with placebo plus paclitaxel in patients with HER2-overexpressing metastatic breast cancer (MBC). PATIENTS AND METHODS: This phase III, randomized, double-blind study assessed the efficacy and safety of lapatinib plus paclitaxel compared with placebo plus paclitaxel in patients with newly diagnosed HER2-positive MBC. The primary end point was OS. Secondary end points included progression-free survival (PFS), overall response rate (ORR), clinical benefit rate, and safety. RESULTS: The addition of lapatinib to paclitaxel significantly improved OS versus paclitaxel (treatment hazard ratio [HR], 0.74; 95% CI, 0.58 to 0.94; P = .0124); median OS was 27.8 versus 20.5 months, respectively. Median PFS was prolonged by 3.2 months, from 6.5 months with placebo plus paclitaxel to 9.7 months with lapatinib plus paclitaxel (HR, 0.52; 95% CI, 0.42 to 0.64; stratified log-rank P < .001). ORR was significantly higher with lapatinib plus paclitaxel compared with placebo plus paclitaxel (69% v 50%, respectively; P < .001). The incidence of grades 3 and 4 diarrhea and neutropenia was higher in the lapatinib plus paclitaxel arm. Only 4% of patients in this group reported febrile neutropenia. Cardiac events were low grade, asymptomatic, and mostly reversible. The incidence of hepatic events was similar in both arms. There were no fatal adverse events in the lapatinib plus paclitaxel arm. CONCLUSION: This trial demonstrated that lapatinib combined with paclitaxel offers a significant and clinically meaningful survival advantage over paclitaxel alone in patients with HER2-positive MBC.

Phase II study evaluating lapatinib in combination with nab-paclitaxel in HER2-overexpressing metastatic breast cancer patients who have received no more than one prior chemotherapeutic regimen.

Lapatinib, an oral, reversible inhibitor of epidermal growth factor receptor and human epidermal growth factor receptor 2 (HER2) tyrosine kinase, has proven antitumor activity in HER2-positive metastatic breast cancer (MBC). Nanoparticle albumin-bound paclitaxel (nab-paclitaxel) is indicated for the treatment of breast cancer after failure of combination chemotherapy for metastatic disease or relapse within 6 months of adjuvant chemotherapy. This was an open-label, single-arm, multicenter, Phase II study to evaluate the efficacy and safety of nab-paclitaxel plus lapatinib in women with HER2 over-expressing MBC who had received no more than one prior chemotherapeutic regimen. The primary efficacy endpoint was the overall response rate (ORR). This was defined as the percentage of patients having either a complete response (CR) or partial response (PR). Secondary efficacy endpoints included progression-free survival (PFS), overall survival, duration of response (DoR), time to response (TTR), and time to progression (TTP). Investigator-assessed ORR was 53 % (n = 32, 95 % confidence interval (CI): 40.7-66.0) with the majority of patient responses demonstrating a PR (47 %). Four (7 %) patient responses demonstrated a CR, and ten (17 %) a stable disease. The median Kaplan-Meier estimate of investigator-assessed PFS, DoR, TTR, and TTP was 39.7 weeks (95 % CI 34.1-63.9), 48.7 weeks (95 % CI 31.7-57.1), 7.8 weeks (95 % CI 7.4-8.1), and 41 weeks (95 % CI 39.1-64.6), respectively. Lapatinib 1,000 mg with nab-paclitaxel 100 mg/m(2) IV is feasible with manageable and predictable toxicity and an ORR of 53 % comparing favorably with other HER2-based combinations in this setting.

A single-arm phase II trial of first-line paclitaxel in combination with lapatinib in HER2-overexpressing metastatic breast cancer.

INTRODUCTION: Lapatinib, an orally active tyrosine kinase inhibitor of epidermal growth factor receptor ErbB1 (EGFR) and ErbB2 (HER2), has activity as monotherapy and in combination with chemotherapy in HER2-overexpressing metastatic breast cancer (MBC). METHODS: This phase II single-arm trial assessed the safety and efficacy of first-line lapatinib in combination with paclitaxel in previously untreated patients with HER2-overexpressing MBC. The primary endpoint was the overall response rate (ORR). Secondary endpoints were the duration of response (DoR), time to response, time to progression, progression-free survival (PFS), overall survival, and the incidence and severity of adverse events. All endpoints were investigator- and independent review committee (IRC)-assessed. RESULTS: The IRC-assessed ORR was 51% (29/57 patients with complete or partial response) while the investigator-assessed ORR was 77% (44/57). As per the IRC, the median DoR was 39.7 weeks, and the median PFS was 47.9 weeks. The most common toxicities were diarrhea (56%), neutropenia (44%), rash (40%), fatigue (25%), and peripheral sensory neuropathy (25%). CONCLUSIONS: First-line lapatinib plus paclitaxel for HER2-overexpressing MBC produced an encouraging ORR with manageable toxicities. This combination may be useful in first-line treatment for patients with HER2-overexpressing MBC and supports the ongoing evaluation of this combination as first-line therapy in HER2-overexpressing MBC.

Phase II study to evaluate the efficacy and safety of neoadjuvant lapatinib plus paclitaxel in patients with inflammatory breast cancer.

PURPOSE: We conducted a phase II, open-label, multicenter study to evaluate the efficacy, safety, and tolerability of daily lapatinib plus weekly paclitaxel in treatment-naïve patients with inflammatory breast cancer (IBC). PATIENTS AND METHODS: The primary end point was pathologic complete response (pCR). Secondary end points included combined clinical response rate (based on Response Evaluation Criteria in Solid Tumors (RECIST) criteria and clinically evaluable skin disease criteria). Patients were assigned to either cohort A (human epidermal growth factor receptor 2 [HER2] 2+ or 3+ by immunohistochemistry [IHC] or fluorescent in situ hybridization [FISH] -amplified +/- epidermal growth factor receptor [EGFR] expression) or cohort B (HER2-negative/EGFR-positive). A subpopulation of cohort A considered HER2-positive by the current definition of overexpression (3+ by IHC or FISH-amplified) was also analyzed. Patients received lapatinib at 1,500 mg/d for 14 days, then lapatinib at 1,500 mg/d plus weekly paclitaxel (80 mg/m(2)) for 12 weeks, followed by surgical resection or additional chemotherapy. RESULTS: Forty-nine women were enrolled (cohort A, n = 42; cohort B, n = 7). Cohort B was terminated because of slow accrual and lack of efficacy observed in IBC patients with HER2-negative/EGFR-positive tumors enrolled onto the parallel study, EGF103009. pCR occurred in 18.2% (95% CI, 5.2% to 40.3%) of cohort A patients. Combined clinical response rate was 78.6% (95% CI, 63.2% to 89.7%) in all cohort A patients and 78.1% (95% CI, 60.0% to 90.7%) in the HER2-positive subset. Common adverse events included diarrhea, rash, alopecia, and nausea (> 50% of patients in both cohorts). The incidence of grade 3 diarrhea was 55%. CONCLUSION: Lapatinib monotherapy for 14 days followed by lapatinib plus paclitaxel for 12 weeks provided clinical benefit in IBC patients with HER2-overexpressing tumors without unexpected toxicity.

Lapatinib monotherapy in patients with HER2-overexpressing relapsed or refractory inflammatory breast cancer: final results and survival of the expanded HER2+ cohort in EGF103009, a phase II study.

BACKGROUND: Inflammatory breast cancer is an aggressive and biologically distinct form with a higher frequency of HER2 overexpression than other breast cancers. For patients with resistance to conventional anthracycline or taxane and trastuzumab treatment, options are limited. Lapatinib, an oral reversible inhibitor of epidermal growth factor receptor tyrosine kinases, previously had a 50% response rate in a cohort of 30 patients with HER2-overexpressing (HER2+) recurrent or anthracycline-refractory inflammatory breast cancer. We aimed to assess efficacy of lapatinib in an expanded cohort of patients with relapsed or refractory HER2+ disease. METHODS: From March, 2005, to September, 2007, 126 patients with relapsed or refractory HER2+ inflammatory breast cancer were treated with lapatinib 1500 mg once daily in a non-randomised, open-label, phase II study. Pretreatment tumour biopsies were done to verify pathological features of inflammatory breast cancer. Skin disease was assessed every 4 weeks, and response in sites of measurable locally advanced or metastatic disease were assessed by response evaluation in solid tumours (RECIST) criteria every 8 weeks. The primary aim was to assess combined objective response rate, by clinically evaluable skin disease criteria and RECIST, if applicable. Analyses were done by intention to treat; patients with missing data were treated as non-responders. This study is registered with ClinicalTrials.gov, number NCT00105950. FINDINGS: Clinical presentation and biomarker analysis showed a tumour molecular profile consistent with inflammatory breast cancer. No patients had complete response. 49 patients (39%; 95% CI 30-48) had partial response. Median progression-free survival was 14.6 weeks (95% CI 12.1-16.0), with median duration of response of 20.9 weeks (12.7-32.1). Likelihood of response to lapatinib was not affected by previous treatment with trastuzumab. 130 (92%) of 141 patients had at least one adverse event; 45 (32%) had serious adverse events, the most common were dyspnoea (eight patients) and pleural effusion (six). Five patients had fatal adverse events that were possibly treatment related. INTERPRETATION: Lapatinib monotherapy is a potentially effective treatment for relapsed or refractory HER2+ inflammatory breast cancer. FUNDING: GlaxoSmithKline.

Can physicians accurately predict survival time in patients with metastatic cancer? Analysis of RTOG 97-14.

PURPOSE: To determine if physician prediction of survival duration (PSD) is accurate for patients with metastatic breast or prostate cancer. METHODS: Radiation Therapy Oncology Group 9714 (RTOG 9714) was a randomized comparison of radiotherapy schedules for treatment of bone metastases. The treating physician assigned a baseline Karnofsky Performance Score (KPS) and predicted survival duration at study entry. Patients completed the Functional Assessment of Cancer Therapy (FACT). These three were compared to actual survival time. RESULTS: Eight hundred ninety-eight patients were eligible and analyzable. Actual median survival was 9.3 months. The median PSD was 12 months. PSD, KPS, and FACT were all moderately correlated with actual survival. Patients with higher KPS had a longer survival time (882 patients, Spearman's rho = 0.259, p < 0.0001). The median survival of the 618 expired patients is 6.5 months (PSD was 12 months). The PSD was within 1 month of actual survival in 61 (10%), with 177 (29%) patients surviving more than 1 month longer than predicted and 375 (61%) surviving more than 1 month less than predicted. A univariate analysis of actual overall survival was performed, dividing the PSD into 4 groups. For predicted survivals of 6 months or less, less than 6 to less than 12 months, 12 months, and more than 12 months, median actual survivals were 7.0, 7.2, 9.7. and 13.5 months (p < 0.0001). CONCLUSIONS: KPS, FACT scores, and PSD all are correlated with actual survival. Physicians on this study were able to predict which patients would have longer survival times, although prediction of survival was optimistic compared to actual survival by an average of 3 months.

Phase II study of predictive biomarker profiles for response targeting human epidermal growth factor receptor 2 (HER-2) in advanced inflammatory breast cancer with lapatinib monotherapy.

PURPOSE: Inflammatory breast cancer (IBC) is one of the most aggressive forms of breast cancer. Lapatinib, an oral reversible inhibitor of epidermal growth factor receptor (EGFR) and human EGFR 2 (HER-2), demonstrated clinical activity in four of five IBC patients in phase I trials. We conducted a phase II trial to confirm the sensitivity of IBC to lapatinib, to determine whether response is HER-2 or EGFR dependent, and to elucidate a molecular signature predictive of lapatinib sensitivity. PATIENTS AND METHODS: Our open-label multicenter phase II trial (EGF103009) assessed clinical activity and safety of lapatinib monotherapy in patients with recurrent or anthracycline-refractory IBC. Patients were assigned to cohorts A (HER-2-overexpressing [HER-2+]) or B(HER-2-/EGFR+) and fresh pretreatment tumor biopsies were collected. RESULTS: Forty-five patients (30 in cohort A; 15 in cohort B) received lapatinib 1,500 mg once daily continuously. Clinical presentation and biomarker analyses demonstrated a tumor molecular signature consistent with IBC. Lapatinib was generally well tolerated, with primarily grade 1/2 skin and GI toxicities. Fifteen patients (50%) in cohort A had clinical responses to lapatinib in skin and/or measurable disease (according to Response Evaluation Criteria in Solid Tumors) compared with one patient in cohort B. Within cohort A, phosphorylated (p) HER-3 and lack of p53 expression predicted for response to lapatinib (P < .05). Tumors coexpressing pHER-2 and pHER-3 were more likely to respond to lapatinib (nine of 10 v four of 14; P = .0045). Prior trastuzumab therapy and loss of phosphate and tensin homolog 10 (PTEN) did not preclude response to lapatinib. CONCLUSION: Lapatinib is well tolerated with clinical activity in heavily pretreated HER-2+, but not EGFR+/HER-2-, IBC. In this study, coexpression of pHER-2 and pHER-3 in tumors seems to predict for a favorable response to lapatinib. These findings warrant further investigation of lapatinib monotherapy or combination therapy in HER-2+ IBC.

Prognostic value of abnormal p53 expression in locally advanced prostate cancer treated with androgen deprivation and radiotherapy: a study based on RTOG 9202.

PURPOSE: The goal of this study was to verify the significance of p53 as a prognostic factor in Radiation Therapy Oncology Group 9202, which compared short-term androgen deprivation (STAD) with radiation therapy (RT) to long-term androgen deprivation + RT in men with locally advanced prostate cancer (Pca). METHODS AND MATERIALS: Tumor tissue was sufficient for p53 analysis in 777 cases. p53 status was determined by immunohistochemistry. Abnormal p53 expression was defined as 20% or more tumor cells with positive nuclei. Univariate and multivariate Cox proportional hazards models were used to evaluate the relationships of p53 status to patient outcomes. RESULTS: Abnormal p53 was detected in 168 of 777 (21.6%) cases, and was significantly associated with cause-specific mortality (adjusted hazard ratio [HR] = 1.89; 95% confidence interval (CI) 1.14 - 3.14; p = 0.014) and distant metastasis (adjusted HR = 1.72; 95% CI 1.13-2.62; p = 0.013). When patients were divided into subgroups according to assigned treatment, only the subgroup of patients who underwent STAD + RT showed significant correlation between p53 status and cause-specific mortality (adjusted HR = 2.43; 95% CI = 1.32-4.49; p = 0.0044). When patients were divided into subgroups according to p53 status, only the subgroup of patients with abnormal p53 showed significant association between assigned treatment and cause-specific mortality (adjusted HR = 3.81; 95% CI 1.40-10.37; p = 0.0087). CONCLUSIONS: Abnormal p53 is a significant prognostic factor for patients with prostate cancer who undergo short-term androgen deprivation and radiotherapy. Long-term androgen deprivation may significantly improve the cause-specific survival for those with abnormal p53.

Prognostic value of p16 in locally advanced prostate cancer: a study based on Radiation Therapy Oncology Group Protocol 9202.

PURPOSE: Deregulation of the retinoblastoma (RB) pathway is commonly found in virtually all known human tumors. p16, the upstream regulator of RB, is among the most commonly affected member of this pathway. In the present study, we examined the prognostic value of p16 expression in men with locally advanced prostate cancer who were enrolled on Radiation Therapy Oncology Group protocol 9202. PATIENTS AND METHODS: RTOG 9202 was a phase III randomized study comparing long-term (LT) versus short-term (ST) androgen-deprivation therapy (AD). Of the 1,514 eligible cases, 612 patients had adequate tumor material for p16 analysis. Expression levels of p16 were determined by immunohistochemistry (IHC). IHC staining was scored quantitatively using an image analysis system. RESULTS: On multivariate analysis, intact p16 expression was significantly associated with decreased rate of distant metastases (P = .0332) when both STAD and LTAD treatment arms were considered together. For patients with intact (high levels of immunostaining) p16 (mean p16 index > 81.3%), LTAD plus radiotherapy (RT) significantly improved prostate cancer survival (PCS) compared with STAD plus RT (P = .0008) and reduced the frequency of distant metastasis (P = .0069) compared with STAD plus RT. In contrast, for patients with tumors demonstrating p16 loss (low levels of immunostaining, mean p16 index < or = 81.3%), LTAD plus RT significantly improved biochemical no evidence of disease survival over STAD (P < .0001) primarily by decreasing the frequency of local progression (P = .02), as opposed to distant metastasis, which was the case in the high-p16 cohort. CONCLUSION: Low levels of p16 on image analysis appear to be associated with a significantly higher risk of distant metastases among all study patients. p16 expression levels also appear to identify patients with locally advanced prostate cancer with distinct patterns of failure after LTAD.

An update of the phase III trial comparing whole pelvic to prostate only radiotherapy and neoadjuvant to adjuvant total androgen suppression: updated analysis of RTOG 94-13, with emphasis on unexpected hormone/radiation interactions.

PURPOSE: This trial was designed to test the hypothesis that total androgen suppression and whole pelvic radiotherapy (WPRT) followed by a prostate boost improves progression-free survival (PFS) by > or =10% compared with total androgen suppression and prostate only RT (PORT). This trial was also designed to test the hypothesis that neoadjuvant hormonal therapy (NHT) followed by concurrent total androgen suppression and RT improves PFS compared with RT followed by adjuvant hormonal therapy (AHT) by > or =10%. METHODS AND MATERIALS: Patients eligible for the study included those with clinically localized adenocarcinoma of the prostate and an elevated prostate-specific antigen level of <100 ng/mL. Patients were stratified by T stage, prostate-specific antigen level, and Gleason score and were required to have an estimated risk of lymph node involvement of >15%. RESULTS: The difference in overall survival for the four arms was statistically significant (p = 0.027). However, no statistically significant differences were found in PFS or overall survival between NHT vs. AHT and WPRT compared with PORT. A trend towards a difference was found in PFS (p = 0.065) in favor of the WPRT + NHT arm compared with the PORT + NHT and WPRT + AHT arms. CONCLUSIONS: Unexpected interactions appear to exist between the timing of hormonal therapy and radiation field size for this patient population. Four Phase III trials have demonstrated better outcomes when NHT was combined with RT compared with RT alone. The Radiation Therapy Oncology Group 9413 trial results have demonstrated that when NHT is used in conjunction with RT, WPRT yields a better PFS than does PORT. It also showed that when NHT + WPRT results in better overall survival than does WPRT + short-term AHT. Additional studies are warranted to determine whether the failure to demonstrate an advantage for NHT + WPRT compared with PORT + AHT is chance or, more likely, reflects a previously unrecognized biologic phenomenon.

Activated STAT3 as a correlate of distant metastasis in prostate cancer: a secondary analysis of Radiation Therapy Oncology Group 86-10.

OBJECTIVE: STAT3 participates in the regulation of cellular growth, survival, and oncogenesis. We evaluated the association between activated STAT3 expression and overall survival, disease-specific survival, distant metastasis, and local progression in a cohort of patients treated with either radiotherapy alone or radiotherapy plus short-term androgen blockade. METHODS: A total of 456 assessable patients were included in the Radiation Therapy Oncology Group 86-10 trial. Of these, 62 patients had sufficient tissue for the analysis of STAT3 expression by immunohistochemistry. Nuclear staining was quantified by an image analysis system. RESULTS: No significant difference was found in the distribution of clinical characteristics and assigned treatment between the patients available for STAT3 analysis (STAT3 cohort) and the others in the Radiation Therapy Oncology Group 86-10 trial (n = 394). Activated STAT3 correlated inversely with the development of distant metastasis (risk ratio [RR] = 0.81, P = 0.04) but not with overall survival, cause-specific survival, or local progression. Similar results were obtained when the data were dichotomized (ACIS index greater than 29%, RR = 0.41, P = 0.07). On multivariate analysis, activated STAT3 (continuous variable) was an independent predictor of distant metastasis (RR = 0.79, P = 0.04). CONCLUSIONS: Activated STAT3 was inversely related to the development of distant metastasis in prostate cancer. This marker should be evaluated further in a larger cohort of patients.