Lauren McCann

Pazopanib in Locally Advanced or Metastatic Renal Cell Carcinoma: Results of a Randomized Phase III Trial

PURPOSE Pazopanib is an oral angiogenesis inhibitor targeting vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit. This randomized, double-blind, placebo-controlled phase III study evaluated efficacy and safety of pazopanib monotherapy in treatment-naive and cytokine-pretreated patients with advanced renal cell carcinoma (RCC). PATIENTS AND METHODS Adult patients with measurable, locally advanced, and/or metastatic RCC were randomly assigned 2:1 to receive oral pazopanib or placebo. The primary end point was progression-free survival (PFS). Secondary end points included overall survival, tumor response rate (Response Evaluation Criteria in Solid Tumors), and safety. Radiographic assessments of tumors were independently reviewed. Results Of 435 patients enrolled, 233 were treatment naive (54%) and 202 were cytokine pretreated (46%). PFS was significantly prolonged with pazopanib compared with placebo in the overall study population (median, PFS 9.2 v 4.2 months; hazard ratio [HR], 0.46; 95% CI, 0.34 to 0.62; P < .0001), the treatment-naive subpopulation (median PFS 11.1 v 2.8 months; HR, 0.40; 95% CI, 0.27 to 0.60; P < .0001), and the cytokine-pretreated subpopulation (median PFS, 7.4 v 4.2 months; HR, 0.54; 95% CI, 0.35 to 0.84; P < .001). The objective response rate was 30% with pazopanib compared with 3% with placebo (P < .001). The median duration of response was longer than 1 year. The most common adverse events were diarrhea, hypertension, hair color changes, nausea, anorexia, and vomiting. There was no evidence of clinically important differences in quality of life for pazopanib versus placebo. CONCLUSION Pazopanib demonstrated significant improvement in PFS and tumor response compared with placebo in treatment-naive and cytokine-pretreated patients with advanced and/or metastatic RCC.

Pazopanib versus Sunitinib in Metastatic Renal-Cell Carcinoma

BACKGROUND Pazopanib and sunitinib provided a progression-free survival benefit, as compared with placebo or interferon, in previous phase 3 studies involving patients with metastatic renal-cell carcinoma. This phase 3, randomized trial compared the efficacy and safety of pazopanib and sunitinib as first-line therapy. METHODS We randomly assigned 1110 patients with clear-cell, metastatic renal-cell carcinoma, in a 1:1 ratio, to receive a continuous dose of pazopanib (800 mg once daily; 557 patients) or sunitinib in 6-week cycles (50 mg once daily for 4 weeks, followed by 2 weeks without treatment; 553 patients). The primary end point was progression-free survival as assessed by independent review, and the study was powered to show the noninferiority of pazopanib versus sunitinib. Secondary end points included overall survival, safety, and quality of life. RESULTS Pazopanib was noninferior to sunitinib with respect to progression-free survival (hazard ratio for progression of disease or death from any cause, 1.05; 95% confidence interval [CI], 0.90 to 1.22), meeting the predefined noninferiority margin (upper bound of the 95% confidence interval, <1.25). Overall survival was similar (hazard ratio for death with pazopanib, 0.91; 95% CI, 0.76 to 1.08). Patients treated with sunitinib, as compared with those treated with pazopanib, had a higher incidence of fatigue (63% vs. 55%), the hand-foot syndrome (50% vs. 29%), and thrombocytopenia (78% vs. 41%); patients treated with pazopanib had a higher incidence of increased levels of alanine aminotransferase (60%, vs. 43% with sunitinib). The mean change from baseline in 11 of 14 health-related quality-of-life domains, particularly those related to fatigue or soreness in the mouth, throat, hands, or feet, during the first 6 months of treatment favored pazopanib (P<0.05 for all 11 comparisons). CONCLUSIONS Pazopanib and sunitinib have similar efficacy, but the safety and quality-of-life profiles favor pazopanib. (Funded by GlaxoSmithKline Pharmaceuticals; COMPARZ ClinicalTrials.gov number, NCT00720941.).

A randomised, double-blind phase III study of pazopanib in patients with advanced and/or metastatic renal cell carcinoma: Final overall survival results and safety update

BACKGROUND In this randomised phase III study (VEG105192; NCT00334282), pazopanib previously demonstrated statistically and clinically meaningful improvement of progression-free survival versus placebo in patients with advanced/metastatic renal cell carcinoma (mRCC). Final overall survival (OS) and updated safety results are now reported. METHODS Treatment-naive or cytokine-pretreated mRCC patients (n=435) stratified and randomised (2:1) to pazopanib 800 mg daily or placebo, were treated until disease progression, death or unacceptable toxicity. Upon progression, placebo patients could receive pazopanib through an open-label study. Final OS in the intent-to-treat population was analysed using a stratified log-rank test. Rank-preserving structural failure time (RPSFT) and inverse probability of censoring weighted (IPCW) analyses were performed post-hoc to adjust for crossover. FINDINGS The difference in final OS between pazopanib- and placebo-treated patients was not statistically significant (22.9 versus 20.5 months, respectively; hazard ratio [HR]=0.91; 95% confidence interval [CI], 0.71-1.16; one-sided P=.224). Early and frequent crossover from placebo to pazopanib and prolonged duration of crossover treatment confounded the OS analysis. In IPCW analyses, pazopanib decreased mortality (HR=0.504; 95% CI, 0.315-0.762; two-sided P=.002). Similar, albeit non-significant, results were obtained in RPSFT analyses (HR=0.43; 95% CI, 0.215-1.388; two-sided P=.172). Since the last cutoff, cumulative exposure to pazopanib increased by 30%. The pazopanib safety profile showed no new safety signals or changes in the type, frequency and severity of adverse events. INTERPRETATION Although no significant difference in OS was observed in this study, extensive crossover from placebo to pazopanib confounded final OS analysis. Post-hoc analyses adjusting for crossover suggest OS benefit with pazopanib treatment for mRCC patients.

Efficacy and Safety of Pazopanib in Patients With Metastatic Renal Cell Carcinoma

PURPOSE Inactivation of the von Hippel-Lindau gene in clear-cell renal cell carcinomas (RCC) leads to overexpression of hypoxia inducible factor, a transcription factor regulating vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) gene expression. Pazopanib, an angiogenesis inhibitor targeting VEGF receptor, PDGF receptor, and c-KIT, was evaluated in patients with RCC. PATIENTS AND METHODS This phase II study was designed as a randomized discontinuation study but was revised to an open-label study on the recommendation of the data monitoring committee (based on week 12 response rate [RR] of 38% in the first 60 patients). The primary end point was changed from progressive disease rate at 16 weeks postrandomization to RR. Pazopanib 800 mg was administered orally once daily. Pazopanib 800 mg was administered orally once daily. RESULTS The study enrolled 225 patients with metastatic RCC; 155 patients (69%) were treatment naïve, and 70 patients (31%) had received one prior cytokine- or bevacizumab-containing regimen. Overall RR was 35%; median duration of response was 68 weeks. Median progression-free survival (PFS) was 52 weeks. Eastern Cooperative Oncology Group performance status of 0 and time from diagnosis to treatment of more than 1 year were correlated with prolonged PFS. Pazopanib was generally well tolerated. The most common adverse events were diarrhea, fatigue, and hair depigmentation. The most common laboratory abnormalities were elevated AST and ALT. CONCLUSION Pazopanib demonstrated durable activity in patients with advanced RCC and was generally well tolerated in this population. These findings support the further development of pazopanib in advanced RCC.

Pazopanib Efficacy in Renal Cell Carcinoma: Evidence for Predictive Genetic Markers in Angiogenesis-Related and Exposure-Related Genes

PURPOSE Pazopanib, an oral angiogenesis inhibitor, is approved for the treatment of advanced renal cell carcinoma (RCC). Response to pazopanib monotherapy varies between patients, and no validated biomarkers predictive of treatment outcome have been identified. We tested the hypothesis that this variability is partially dependent on germline genetic variants that may affect pazopanib exposure or angiogenesis pathways. PATIENTS AND METHODS Twenty-seven functional polymorphisms within 13 genes were evaluated in 397 patients with RCC. Genetic association with progression-free survival (PFS) and objective response rate (RR) was analyzed using the Cox proportional hazards model and proportional odds model, respectively. RESULTS Three polymorphisms in IL8 and HIF1A and five polymorphisms in HIF1A, NR1I2, and VEGFA showed nominally significant association (P ≤ .05) with PFS and RR, respectively. Compared with the wild-type AA genotype (median PFS, 48 weeks), the IL8 2767TT variant genotype showed inferior PFS (27 weeks, P = .009). The HIF1A 1790AG genotype was associated with inferior PFS and reduced RR, compared with the wild-type GG genotype (median PFS, 20 v 44 weeks; P = .03; RR, 30% v 43%, P = .02). Reductions in RR were detected for the NR1I2 -25385TT genotype, compared with the wild-type CC genotype (37% v 50%, P = .03), and for the VEGFA -1498CC genotype compared with the TT genotypes (33% v 51%). CONCLUSION Germline variants in angiogenesis- and exposure-related genes may predict treatment response to pazopanib monotherapy in patients with RCC. If validated, these markers may explain why certain patients fail antiangiogenesis therapy and they may support the use of alternative strategies to circumvent this issue.

Overall survival in renal-cell carcinoma with pazopanib versus sunitinib.

Survival results are now mature for a noninferiority trial comparing pazopanib with sunitinib in renal-cell carcinoma. Median survival was 42.5 months with pazopanib and 43.6 months with sunitinib, a difference that wasnot significant.

Patient preference between pazopanib (Paz) and sunitinib (Sun): Results of a randomized double-blind, placebo-controlled, cross-over study in patients with metastatic renal cell carcinoma (mRCC)—PISCES study, NCT 01064310.

CRA4502 Background: Increasingly pt reported outcomes are being added to traditional efficacy outcomes to understand the clinical relevance of toxicity differences between therapies. This study investigated if tolerability differences were significant enough to lead a patient to prefer continuing their treatment with Paz or Sun. METHODS Pts with mRCC were randomized 1:1 to receive as first line treatment blinded 800mg Paz for 10 weeks followed by a 2-week washout and then 50mg Sun for 10 weeks (4/2 weeks schedule) or vice versa. Pts were stratified based on ECOG performance status (0 vs 1) and number of metastatic sites (0/1 vs 2+). The primary endpoint, patient preference assessed at 22 weeks, was compared using Prescotts test (α=0.10). At least 102 of 160 planned pts were required to complete the preference questionnaire to provide 80% power to detect a preference for one drug over another of 50% vs 30% with 20% expressing no preference. Other endpoints included physician preference, safety, QoL, pharmacokinetics and biomarkers. RESULTS Of 168 randomized pts, 126 completed the preference questionnaire. In the protocol-driven primary analysis (n=114), Paz was preferred by 70% of pts, Sun by 22% and 8% had no preference. After adjusting for a modest sequence effect, the difference in preference was 49% [90% CI 37.0 - 61.5% p <0.001] in favor of Paz. All pre-planned sensitivity analyses conducted were statistically significant in favor of Paz, including one which imputed Sun for all unavailable pt preference data. The most common reasons for Paz preference were better QoL and less fatigue. 60% of physicians preferred Paz vs 21% for Sun vs 19% no preference. Adverse events (AE) were in line with known profiles for both drugs. Pts on Paz had fewer dose reductions (13% vs 20%) and interruptions (6% vs 12%) vs Sun, mostly due to AE. There was less fatigue on Paz as assessed by FACIT-Fatigue; treatment difference of 2.49, p=0.002. Investigator assessed response (RECIST 1.1) was 22% with Paz vs 24% with Sun, p=0.87. CONCLUSIONS This innovative trial design clearly demonstrates the better tolerability of Paz compared to Sun.

Health-related quality of life in patients with advanced renal cell carcinoma receiving pazopanib or placebo in a randomised phase III trial

BACKGROUND In a double-blind, randomised phase III trial of advanced renal cell carcinoma patients, pazopanib 800mg QD (n=290) versus placebo (n=145) significantly prolonged progression-free survival (hazard ratio (HR)=0.46, 95% confidence interval [CI] 0.34-0.62, p-value<0.0001), without important differences in health-related quality of life (HRQoL). This post-hoc analysis evaluated time to HRQoL deterioration and whether tumour response/stabilisation was associated with HRQoL improvement. METHODS HRQoL was assessed using EORTC QLQ-C30 and EQ-5D. Effect of pazopanib on time to ⩾20% decline from baseline in summary scores was estimated for all patients and by prior treatment. Analyses were conducted for different HRQoL deterioration thresholds. HRQoL changes were stratified by benefit and compared: complete response (CR) or partial response (PR) versus progressive disease (PD); CR/PR versus stable disease (SD), and SD versus PD. RESULTS There was a trend for pazopanib patients to be less likely than placebo patients to experience ⩾20% HRQoL deterioration in EORTC-QLQ-C-30 global health status/QOL scale (HR=0.77; 95% CI 0.57-1.03, not significant). Results by prior treatment and different HRQoL deterioration thresholds were similar. Patients with CR/PR and SD experienced significantly less HRQoL deterioration than those with PD (p<0.001, p=0.0024, respectively); mean differences between patients with CR/PR and PD exceeded the pre-determined minimally important difference (MID). Differences between patients with SD and PD did not exceed pre-determined MID. Results were generally consistent across treatment and EQ-5D summary scores. CONCLUSION Results support the favourable benefit-risk profile of pazopanib and suggest patients experiencing tumour response/stabilisation also may have better HRQoL compared to those without this response.

IL8 polymorphisms and overall survival in pazopanib- or sunitinib-treated patients with renal cell carcinoma

Background:We evaluated germline single nucleotide polymorphisms (SNPs) for association with overall survival (OS) in pazopanib- or sunitinib-treated patients with advanced renal cell carcinoma (aRCC).Methods:The discovery analysis tested 27 SNPs within 13 genes from a phase III pazopanib trial (N=241, study 1). Suggestive associations were then pursued in two independent datasets: a phase III trial (COMPARZ) comparing pazopanib vs sunitinib (N=729, study 2) and an observational study of sunitinib-treated patients (N=89, study 3).Results:In study 1, four SNPs showed nominally significant association (P≤0.05) with OS; two of these SNPs (rs1126647, rs4073) in IL8 were associated (P≤0.05) with OS in study 2. Because rs1126647 and rs4073 were highly correlated, only rs1126647 was evaluated in study 3, which also showed association (P≤0.05). In the combined data, rs1126647 was associated with OS after conservative multiple-test adjustment (P=8.8 × 10−5; variant vs reference allele hazard ratio 1.32, 95% confidence interval: 1.15–1.52), without evidence for heterogeneity of effects between studies or between pazopanib- and sunitinib-treated patients.Conclusions:Variant alleles of IL8 polymorphisms are associated with poorer survival outcomes in pazopanib- or sunitinib-treated patients with aRCC. These findings provide insight in aRCC prognosis and may advance our thinking in development of new therapies.

Concomitant use of pazopanib and simvastatin increases the risk of transaminase elevations in patients with cancer

Alanine aminotransferase (ALT) elevations were reported in oncology trials of the oral angiogenesis inhibitor pazopanib [1]. Statins, which are widely used to treat hypercholesterolemia [2], are also associated with ALT elevations. As pazopanib and statins are substrates for the same key metabolizing enzymes [e.g. cytochrome P450 3A4 (CYP3A4)] and drug transporters [e.g. P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP)] [2–3], it is plausible that concomitant administration of pazopanib and statins may alter their systemic and/or hepatic exposures, leading to increased toxicities such as liver injury. Using individual patient data from 11 pazopanib clinical studies for the treatment of cancer (n = 976), we evaluated the effects of concomitant pazopanib and statin use on the incidence of ALT elevation [≥3 × upper limit of normal (ULN)]. The incidence of ALT≥ 3 × ULN was 21% in patients who received both pazopanib and any statin and 14% in patients who did not receive statins (P = 0.10; Table 1). Simvastatin and atorvastatin were the two most commonly used statins in this patient population. The incidence of ALT≥ 3 × ULN (27%) was significantly higher in simvastatin users than in patients who did not receive statins (P = 0.04; Table 1). Although the incidence of ALT≥ 3 × ULN was also higher in atorvastatin users (17%) than in patients who did not receive statins (14%), this difference did not reach statistical significance (P = 0.59). Among patients with ALT≥ 3 × ULN who received both pazopanib and simvastatin, ALT recovery to <2.5 × ULN (grade ≤1 by common toxicity criteria v3) was documented for 10/11 patients (91%) after either (i) no alteration for pazopanib and simvastatin therapy (n = 2); (ii) discontinuation of simvastatin only (n = 2); (iii) discontinuation of pazopanib only (n = 4); or (iv) discontinuation of both simvastatin and pazopanib (n = 2). There were insufficient follow-up ALT data to assess recovery for the one remaining patient after pazopanib was discontinued. The ALT recovery rate (to <2.5 × ULN) for patients receiving concomitant pazopanib and simvastatin was comparable with that seen in the larger group of pazopanib-treated study patients with renal cell carcinoma who had ALT≥ 3 × ULN (96/106, 91%) [4]. Exploratory pharmacogenetic analysis revealed that the ABCG2 (BCRP) 421C>A polymorphism may be associated with ALT elevation in patients taking pazopanib and simvastatin. Those with the variant 421C>A allele had a higher incidence of ALT≥ 3 × ULN (5/7, 71%) compared with patients with wild-type genotype (2/21, 10%; odds ratio = 19.6, 95% confidence interval 1.9–231.6; P = 0.004). This polymorphism was not associated with ALT elevations in pazopanib-treated patients without concurrent use of statins. This study showed that concomitant use of pazopanib and simvastatin increased the risk of transaminase elevations in patients with cancer. In addition to implementing the recommended dose modification guidelines for pazopanib, discontinuation of simvastatin should be considered to manage the risk of liver injury in cancer patients receiving both medications. Furthermore, hepatotoxicity/transaminase elevations have been reported in patients receiving other multi-tyrosine kinase inhibitors (e.g. imatinib, erlotinib, lapatinib, nilotinib, and sunitinib) that are also metabolized primarily by CYP3A4 [5]. The effect of concomitant administration of these tyrosine kinase inhibitors and statins on potential hepatotoxicity remains to be determined.