Randomised double-blind phase 3 clinical study testing impact of atorvastatin on prostate cancer progression after initiation of androgen deprivation therapy: study protocol

INTRODUCTION

Blood cholesterol is likely a risk factor for prostate cancer prognosis and use of statins is associated with lowered risk of prostate cancer recurrence and progression. Furthermore, use of statins has been associated with prolonged time before development of castration resistance (CR) during androgen deprivation therapy (ADT) for prostate cancer. However, the efficacy of statins on delaying castration-resistance has not been tested in a randomised placebo-controlled setting.This study aims to test statins' efficacy compared to placebo in delaying development of CR during ADT treatment for primary metastatic or recurrent prostate cancer. Secondary aim is to explore effect of statin intervention on prostate cancer mortality and lipid metabolism during ADT.

METHODS AND ANALYSIS

In this randomised placebo-controlled trial, a total of 400 men with de novo metastatic prostate cancer or recurrent disease after primary treatment and starting ADT will be recruited and randomised 1:1 to use daily 80 mg of atorvastatin or placebo. All researchers, study nurses and patients will be blinded throughout the trial. Patients are followed until disease recurrence or death. Primary outcome is time to formation of CR after initiation of ADT. Serum lipid levels (total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and trigyserides) are analysed to test whether changes in serum cholesterol parameters during ADT predict length of treatment response. Furthermore, the trial will compare quality of life, cardiovascular morbidity, changes in blood glucose and circulating cell-free DNA, and urine lipidome during trial.

ETHICS AND DISSEMINATION

This study is approved by the Regional ethics committees of the Pirkanmaa Hospital District, Science centre, Tampere, Finland (R18065M) and Tarto University Hospital, Tarto, Estonia (319/T-6). All participants read and sign informed consent form before study entry. After publication of results for the primary endpoints, anonymised summary metadata and statistical code will be made openly available. The data will not include any information that could make it possible to identify a given participant.

TRIAL REGISTRATION NUMBER

Clinicaltrial.gov: NCT04026230, Eudra-CT: 2016-004774-17, protocol code: ESTO2, protocol date 10 September 2020 and version 6.

Abstract 3293: Serum and intraprostatic lipidome level shift during statin use among prostate cancer patients

Prostate cancer patients using cholesterol-lowering statins have 30 % lower risk of prostate cancer death compared to non-users. The effect is attributed to the inhibition of the mevalonate pathway which is active in prostate cancer cells. Statin intervention also causes lipidome level shift in the serum. However, it is unknown whether statin intervention also affects intraprostatic lipidome (IPL) as well.

We studied the lipidome level shift among Finnish males diagnosed with prostate cancer and scheduled for radical prostatectomy in a randomized, placebo-controlled double-blind clinical trial. Total number of participants was 86 where 41 were given placebo and 45 were treated daily with 80 mg of atorvastatin (AS) for a median of 27 days preceeding the surgery. The serum lipidome (SL) level was measured before and after the intervention using mass spectrometer, whereas the IPL level was measured after the surgery. SL contains 213 lipid aggregates, while the IPL contains 4,652 single-molecule lipids. Furthermore, we investigated if the baseline lipidome level or the shift during intervention displays relationship with tumor Gleason grade, PSA level, Ki67 proliferation marker level in the tissue, and / or intraprostatic inflammation.

The relationship was studied using supervised random forest classification (RFC), and linear regression (LR) adjusted for age and body mass index. RFC robustness with respect to the intrinsic randomization was measured by repeating RFC 100 times. The 4,652 IPL molecules were reduced to 101 after limiting analysis to ones demonstrating statistically significant difference between placebo and AS group. The statistically significant difference was tested with t-test and Mann-Whitney test depending on the sample distribution.

The SL difference before-after intervention separates the two groups with extremely low RFC error of 8.1 – 9.3 %. This indicates that the intervention has systematically altered the SL. The RFC error for the IPL was 29 – 37.7 % and does not separate the placebo and AS group as well as in the serum. Thus, the AS effect on IPL is not as strong as in the serum, although a suggestion of differing lipid profiles by treatment arm was observed. One serum lipid, Glycoproteinacetylsmainlya1acidglycoprotein (GP), did show a clear linear relationship with the PSA level change; however, it was independent of the AS intervention. Baseline SL did not predict high-grade prostate cancer, Ki67 level, or inflammation level in general, according to RFC or LR.

AS intervention displays a clear effect on SL level, but only a modest effect on the IPL. Our finding suggests the AS affects the lipids in the prostate as well. GP serum lipid aggregate shows linear relationship with the PSA level change but it is independent of AS intervention. IPL does not correlate with the tumor Gleason grade or Ki-67 proliferation activity.

Citation Format: Paavo V. Raittinen, Kati Niemistö, Seppo Auriola, Pauliina Ilmonen, Teemu J. Murtola. Serum and intraprostatic lipidome level shift during statin use among prostate cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3293.

Abstract 4226: Association between NSAID, statins, and bisphosphonates and prostate cancer survival during androgen deprivation therapy

We study the association between non-steroidal anti-inflammatory drugs (NSAIDs), Statins, and Bisphosphonates (BPs), and prostate cancer (PCa) survival during androgen deprivation therapy (ADT). STAMPEDE trial has demonstrated better PCa-specific survival in men using combination of celecoxib (CEL) and zoledronic acid (ZA) during ADT compared to ADT alone. The mechanism is unclear. ZA inhibits mevalonate pathway (MevP) previously linked with cancer growth. We evaluated PCa survival among men on ADT and simultaneously using BPs including ZA or statins, another drug group inhibiting MevP, and NSAIDs including CEL. We hypothesized that combined use of a MevP inhibitor and NSAID would be associated with improved PCa survival.

Our study cohort includes 4,428 men from the Finnish Randomized Study of PCa Screening (FinRSPC) initiating ADT in 1995-2015. Cox proportional hazards model with adjustment for age, FinRSPC study arm, tumor clinical characteristics and co-morbidities (obtained from national registries) was used to calculate HRs and 95% CI for PCa death. Medication use was analyzed as time-dependent variable.

Compared to non-users, the risk of PCa death was increased in users of NSAIDs or acetaminophen, and lowered in statin users. Use of BPs or coxibs alone were not associated with the risk. Coxibs and statins together were associated with lowered risk to a similar degree as statins alone. No statistically significant risk differences were observed for other combinations.

Statin users with high-risk prostate cancer undergoing ADT have lowered risk of PCa death. NSAID users have increased risk of PCa death, which becomes statistically insignificant when used with statins. Statin and BP use together shows no statistically significant evidence of negating the effects of statin. No clear additive benefit was observed for statins and coxibs together over statins alone. Our findings do not support additive benefits of MevP inhibitor and NSAIDs.

Statistical significance codes: *** : p = 0.001, ** : p = 0.01, * : p = 0.1DrugHR95 % CISignificanceStatin0.780.680.90***Acetylsalisylic acid0.900.761.07Coxib1.070.941.22NSAID1.171.041.31**Acetaminophen1.661.511.82***Bisphosphonate0.790.381.64Bisphosphonate and NSAID0.890.551.42Statin and NSAID1.070.901.27Statin and Bisphosphonate1.140.861.50Coxib and Bisphosphonate0.850.421.74Coxib and Statin0.800.621.02*EAU tumor Risk Group2.662.353.00***

Citation Format: Paavo V. Raittinen, Kirsi Talala, Kimmo Taari, Teuvo L. Tammela, Pauliina Ilmonen, Anssi Auvinen, Teemu J. Murtola. Association between NSAID, statins, and bisphosphonates and prostate cancer survival during androgen deprivation therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4226.