Kelly Mundy

A pharmacodynamic study of rapamycin in men with intermediate to high risk localized prostate cancer

Purpose: Given discrepancies between preclinical and clinical observations of mammalian target of rapamycin (mTOR) inhibition in prostate cancer, we sought to determine the pharmacodynamic effects of the mTOR/TORC1 inhibitor rapamycin in men with intermediate- to high-risk prostate cancer undergoing radical prostatectomy. Experimental Design: Rapamycin was given at 3 or 6 mg orally for 14 days before radical prostatectomy in men with multifocal Gleason sum ≥7 prostate cancer; 10 untreated control subjects were included. The primary outcome was inhibition of phosphorylation of ribosomal S6 in posttreatment radical prostatectomy versus pretreatment biopsy tumor tissue, evaluated using a Simon two-stage design for pharmacodynamic efficacy. Results: Thirty-two subjects were accrued: 20 at 3 mg, 2 at 6 mg, and 10 controls. No dose-limiting toxicities were observed at 3 mg; however, two of two men enrolled at 6 mg experienced dose-limiting toxicities including thrombocytopenia and fever with grade 3 stomatitis. Adverse events observed at 3 mg included stomatitis, rash, ileus, and neutropenia. Pharmacodynamic studies showed tumor S6 phosphorylation inhibition in 50% of 10 evaluable rapamycin-treated men with sufficient paired tissue [median 58% inhibition (P = 0.049) versus 2% inhibition in controls (P = 0.75)] with no significant effect on AKT activity. We observed no change in Ki-67 or caspase-3 cleavage but noted a reduction in cytoplasmic p27 staining with increased nuclear localization with rapamycin treatment. Prostate tissue rapamycin concentrations were 3- to 4-fold higher than blood. Conclusions: At 3 mg daily, rapamycin successfully and safely inhibited prostate cancer S6 phosphorylation and achieved relatively high prostate tissue concentrations. No effect on AKT phosphorylation, tumor proliferation, or apoptosis was observed. Clin Cancer Res; 16(11); 3057–66. ©2010 AACR.

A phase 2 multimodality trial of docetaxel/prednisone with sunitinib followed by salvage radiation therapy in men with PSA recurrent prostate cancer after radical prostatectomy.

Background:In men with high Gleason PC and rapid PSA progression after surgery, failure rates remain unacceptably high despite salvage radiation. We explored a novel multimodality approach of docetaxel with anti-angiogenic therapy before salvage radiotherapy (RT).Methods:This was a phase 2 single-arm prospective open-label trial with historic controls. Eligible men had a rising PSA of 0.1–3.0 ng ml−1 within 4 years of radical prostatectomy, no metastases except resected nodal disease, no prior androgen-deprivation therapy (ADT) and Gleason 7–10. Men received four cycles of docetaxel 70 mg m−2 every 3 weeks with low dose prednisone and sunitinib 37.5 mg daily for 14/21 days each cycle, with no ADT. Salvage prostate bed RT (66 Gy) started at day 100. The primary end point was progression-free survival (PFS) rate at 24 months. Safety data, quality of life (QOL) and dose-limiting toxicities (DLTs) were measured over time.Results:Thirty-four men accrued in this multi-institutional clinical trial: 24% of men were node positive, 47% were Gleason 8–10, median PSA at entry was 0.54. The trial was terminated prematurely owing to excess DLTs (nine) including grade 3 hand–foot syndrome (n=4), neutropenic fever (n=2), AST increase (n=1), fatigue (n=1) and vomiting with diarrhea (n=1). PFS rate at 24 months was 51% (95% CI: 33, 67%) with a median PFS of 26.2 months (95% CI: 12.5, —). Six men (17.6%) had an undetectable PSA at 2 years.Conclusions:Sunitinib and docetaxel/prednisone followed by salvage RT resulted in excess pre-specified DLTs. Although nearly half of the men experienced durable disease control, efficacy was not greater than expected with radiation alone. The use of the intermediate end point of PFS in this salvage setting permitted an early decision on further development of this combination.

Phase Ib Trial of Cabazitaxel and Tasquinimod in Men With Heavily Pretreated Metastatic Castration Resistant Prostate Cancer (mCRPC): The CATCH Trial

Tasquinimod is an immunomodulating and anti‐antiangiogenic oral agent with anti‐prostate cancer activity in preclinical studies and in clinical trials of men with metastatic castration resistant prostate cancer (mCRPC), including single agent activity and in combination with taxanes. We sought to identify the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) of tasquinimod in combination with cabazitaxel and prednisone in men with chemorefractory mCRPC.

A phase 2 multimodality trial of docetaxel/prednisone with sunitinib followed by salvage radiation therapy (RT) in men with PSA recurrent prostate cancer (PC) after radical prostatectomy (RP).

35 Background: In men with high grade PC and rapid PSA progression after RP, failure rates are unacceptably high despite salvage RT. Androgen deprivation therapy (ADT) is not curative in this setting and we thus evaluated a novel multi-modality approach of systemic chemotherapy and anti-angiogenic therapy prior to prostate bed salvage RT in a multicenter trial. Methods: Eligible men had a rising PSA of 0.1-3.0 ng/ml within 4 years of RP, no metastatic disease except resected positive nodes, no prior ADT, and Gleason 7-10. Men received 4 cycles of docetaxel 70 mg/m2 q3w with prednisone 5 mg bid and sunitinib 37.5 mg qd for 14/21 days each cycle. Salvage RT (66Gy/33fx) to the prostate bed started at day 100. The primary endpoint was progression-free survival at 2 years (PFS2), defined as a confirmed PSA rise above the post-RT nadir or baseline if no nadir occurred, clinical/radiographic progression, or death from date of enrollment. Safety and dose-limiting toxicities were evaluated. This was a single arm p...

Phase Ib trial of docetaxel, prednisone, and pazopanib, in men with metastatic castration resistant prostate cancer (mCRPC).

275 Background: Docetaxel prednisone (DP) is a standard of care for men with metastatic castrate resistant prostate cancer (mCRPC) with median progression-free survival (PFS) of 4-6 months and overall survival (OS) of 19 months, supporting a need for further treatment options. Pazopanib (PAZO) is a multi-targeted kinase inhibitor of VEGF receptors approved for treatment of kidney cancer and sarcoma. We performed a two center, Phase Ib study of DP + PAZO to evaluate the safety and early efficacy in mCRPC. Methods: This is a 2 site phase 1 DOD Prostate Cancer Clinical Trials Consortium trial of DP + PAZO once daily with ongoing ADT in men with mCRPC. The primary endpoint was safety; secondary endpoints included evaluation of a maximum tolerated dose (MTD) through a dose escalation and expansion design, pharmacokinetic assessments, PSA and radiographic responses, and toxicity. Results: Twenty-five men were treated over 6 dose levels using a 3+3 design. Pegfilgrastim (Neu) was added to the regimen after myelo...

Investigator-initiated pilot study of sunitinib malate in patients with newly diagnosed prostate cancer prior to prostatectomy: A trial of the DoD/PCF Prostate Cancer Clinical Trials Consortium.

4664 Background: Sunitinib malate (Sutent, Pfizer) is an oral multi-targeted tyrosine kinase inhibitor of VEGF/PDGF receptors that may function in part to inhibit prostate tumor growth via anti-angiogenic mechanisms. METHODS We conducted a multi-site study of sunitinib in patients with newly diagnosed, clinically localized prostate cancer prior to prostatectomy. After meeting eligibility requirements (intermediate to high risk, localized prostate cancer, adequate laboratory parameters, no prior treatment for prostate cancer), subjects received sunitinib 50mg PO for 28 days followed by a 1 week washout period followed by either radical retropubic or robot-assisted prostatectomy. Pathologic specimens (pretreatment biopsies and prostatectomy specimens) were evaluated for apoptotic (TUNEL) and proliferation (Ki-67) indices, microvessel density (MVD) and gene expression patterns. RESULTS 31 subjects were enrolled (median age 60 yrs; ECOG=0, biopsy Gleason 3+4=7). Data analysis is complete for 28 subjects. Most common toxicities (>30%) were diarrhea, fatigue, hypertension, mucositis, neutropenia, taste alterations, and thrombocytopenia. Most common grade 3-4 toxicities (> 5%) were hypertension, increased AST/ALT, and neutropenia. Median PSA decline was 13.6% (range -32% to 80%). Median change in Ki-67 was -34% (lower quartile -64% upper quartile +1.3%); median change in TUNEL was 4.5% (lower quartile -76%, upper quartile +286%); and median change in MVD (CD31) was +22% (lower quartile -23%, upper quartile +110%). Gene expression analysis is ongoing. CONCLUSIONS Sunitinib given in the pre-prostastectomy setting appears safe and tolerable with a similar toxicity profile seen in patients with advanced cancer. Changes in proliferation and apoptosis suggest a treatment effect, while increases in MVD suggest a possible rebound effect off of sunitinib.