Randomized Phase II Study Evaluating Akt Blockade with Ipatasertib, in Combination with Abiraterone, in Patients with Metastatic Prostate Cancer with and without PTEN Loss.

PURPOSE: PI3K-Akt-mTOR and androgen receptor (AR) signaling are commonly aberrantly activated in metastatic castration-resistant prostate cancer (mCRPC), with PTEN loss associating with poor prognosis. We therefore conducted a phase Ib/II study of the combination of ipatasertib, an Akt inhibitor, with the CYP17 inhibitor abiraterone in patients with mCRPC.Patients and Methods: Patients were randomized 1:1:1 to ipatasertib 400 mg, ipatasertib 200 mg, or placebo, with abiraterone 1,000 mg orally. Coprimary efficacy endpoints were radiographic progression-free survival (rPFS) in the intent-to-treat population and in patients with PTEN-loss tumors. RESULTS: rPFS was prolonged in the ipatasertib cohort versus placebo, with similar trends in overall survival and time-to-PSA progression. A larger rPFS prolongation for the combination was demonstrated in PTEN-loss tumors versus those without. The combination was well tolerated, with no treatment-related deaths. CONCLUSIONS: In mCRPC, combined blockade with abiraterone and ipatasertib showed superior antitumor activity to abiraterone alone, especially in patients with PTEN-loss tumors.See related commentary by Zhang et al., p. 901.

Randomized phase II trial of Onartuzumab in combination with erlotinib in patients with advanced non-small-cell lung cancer.

PURPOSE: Increased hepatocyte growth factor/MET signaling is associated with poor prognosis and acquired resistance to epidermal growth factor receptor (EGFR) -targeted drugs in patients with non-small-cell lung cancer (NSCLC). We investigated whether dual inhibition of MET/EGFR results in clinical benefit in patients with NSCLC. PATIENTS AND METHODS: Patients with recurrent NSCLC were randomly assigned at a ratio of one to one to receive onartuzumab plus erlotinib or placebo plus erlotinib; crossover was allowed at progression. Tumor tissue was required to assess MET status by immunohistochemistry (IHC). Coprimary end points were progression-free survival (PFS) in the intent-to-treat (ITT) and MET-positive (MET IHC diagnostic positive) populations; additional end points included overall survival (OS), objective response rate, and safety. RESULTS: There was no improvement in PFS or OS in the ITT population (n = 137; PFS hazard ratio [HR], 1.09; P = .69; OS HR, 0.80; P = .34). MET-positive patients (n = 66) treated with erlotinib plus onartuzumab showed improvement in both PFS (HR, .53; P = .04) and OS (HR, .37; P = .002). Conversely, clinical outcomes were worse in MET-negative patients treated with onartuzumab plus erlotinib (n = 62; PFS HR, 1.82; P = .05; OS HR, 1.78; P = .16). MET-positive control patients had worse outcomes versus MET-negative control patients (n = 62; PFS HR, 1.71; P = .06; OS HR, 2.61; P = .004). Incidence of peripheral edema was increased in onartuzumab-treated patients. CONCLUSION: Onartuzumab plus erlotinib was associated with improved PFS and OS in the MET-positive population. These results combined with the worse outcomes observed in MET-negative patients treated with onartuzumab highlight the importance of diagnostic testing in drug development.

Phase I study combining treatment with temsirolimus and sunitinib malate in patients with advanced renal cell carcinoma.

PURPOSE: Concurrent inhibition of multiple oncogenic signaling pathways might improve the efficacy of anticancer agents and abrogate resistance mechanisms. This phase I study evaluated temsirolimus in combination with sunitinib in patients with advanced RCC. PATIENTS AND METHODS: Eligibility included advanced RCC and or= 7 days) were observed in 2 of 3 patients. One patient experienced grade 3 rash during week 3, which led to treatment discontinuation. A second patient had grade 3 thrombocytopenia (platelet count, 48,000/microL), cellulitis, and gout during week 3 and was hospitalized; platelets recovered to 109,000/microL 4 days after discontinuation of protocol therapy. A third patient experienced rash, asthenia, diarrhea, stomatitis, constipation, fever, and rectal hemorrhage, all of which were mild in severity. The study was terminated because of dose-limiting toxicity observed at low starting doses of both agents. CONCLUSION: Concomitant use of I.V. temsirolimus 15 mg weekly and oral sunitinib 25 mg daily (4 weeks on, 2 weeks off) is not recommended.

Phase II trial of lenalidomide in patients with metastatic renal cell carcinoma.

Lenalidomide (CC-5013) is a structural derivative of thalidomide, with antiangiogenic and immunomodulatory effects. Fourteen patients with metastatic renal cell carcinoma (RCC) were enrolled on a phase 2 trial of lenalidomide administered orally at 25 mg daily for 21 days followed by a rest period of 7 days. The best response was stable disease in eight patients (57%) of the 14 evaluable patients. Toxicities included fatigue, hyperglycemia, dyspnea, and myelosuppression with decreased hemoglobin, lymphopenia, and neutropenia. Lenalidomide is tolerable, but no objective responses were observed in this clinical trial.

Targeting von Hippel-Lindau pathway in renal cell carcinoma.

Inheritance of a defective copy of the von Hippel-Lindau (VHL) gene leads to the most common cause of inherited renal cell carcinoma (RCC). In addition, most patients with sporadic RCC have aberrant VHL. In the absence of VHL, hypoxia-inducible factor alpha accumulates, leading to production of several growth factors, including vascular endothelial growth factor and platelet-derived growth factor. We review here the biology of RCC and how a combination of proximal and distal block of VHL/hypoxia-inducible factor alpha pathway by novel targeted agents, including sunitinib, sorafenib, bevacizumab, everolimus, and temsirolimus, has led to significant improvements in progression-free survival.