Mini Oral session
Date
18.09.2020
Chairs
  • Eleni Efstathiou (Houston, TX, United States of America)
  • Andrea Alimonti (Bellinzona, Switzerland)
  • Noel Clarke (London, United Kingdom)
Mini Oral - Genitourinary tumours, prostate Mini Oral session

Open & welcome

Speakers
  • Eleni Efstathiou (Houston, TX, United States of America)
Mini Oral - Genitourinary tumours, prostate Mini Oral session

612MO - Clinical impact of somatic alterations in prostate cancer patients with and without previously known germline BRCA1/2 mutations: Results from PROREPAIR-A study

Presentation Number
612MO
Speakers
  • Rebeca Lozano Mejorada (Madrid, Spain)

Abstract

Background

Germline BRCA2 mutations (gBRCA2) are associated with poor clinical outcomes in prostate cancer (PC), however, the molecular origin of this clinical aggressiveness have not been fully elucidated.

Methods

In this multicentre case-control study, gBRCA2 carriers were matched 1:2 to known non-carriers (NC) by Gleason score and stage at diagnosis (M0 vs M1). A minimum of 60 cases-120 controls were required to prove a 5yrs cause-specific survival (CSS) rate of 60% vs 85%. The primary aim was to confirm the independent prognostic role of gBRCA2 in PC CSS. Secondary aims included to explore the clinical impact of somatic events in BRCA2, RB1, MYC, PTEN and TMPRSS2-ERG by FISH. Kaplan Meier and Cox-regression models were used to identify associations between molecular characteristics and outcomes.

Results

A total of 73 gBRCA2 carriers and 127 NC were eligible. gBRCA2 carriers were younger at diagnosis (p=0.02) and had more often T3/4 (p<0.001) than NC, but no other significant differences were found. gBRCA2 carriers presented more somatic alterations than NC (p<0.001), including BRCA2 loss, RB1 loss and MYC amplification. BRCA2 were frequently co-deleted with RB1 (Pearson correlation 0.96; p=0.001). gBRCA2 mutations were independently associated with CSS (HR 3.70; p=0.008). CSS were shorter in gBRCA2 carriers who also present somatic BRCA2-RB1 codel or MYC amplification compared with gBRCA2 without such alterations. SImilar results were observed in NC (Table). MVA model confirmed the independent prognostic value of somatic BRCA2-RB1 codel (HR 4.13; p=0.004) and MYC amplif (HR 2.27; p=0.033) for CSS.

Median CSS (96%CI), yrs p-value
gBRCA2 gBRCA2 + BRCA2-RB1 codeletion 11.3 (7-2-15.4) 6.3 (2.1-10.6) 0.041
gBRCA2 gBRCA2 + MYC amplification 13.4 (10-16.8) 6 (4.1-7.9) <0.001
NC NC + BRCA2-RB1 codeletion 17.6 (NR) 9.8 (5.9-13.8) <0.001
NC NC + MYC amplification 17.6 (NR) 4.8 (0-10.8) <0.001

Conclusions

PROREPAIR-A is the largest series of gBRCA2 tumors assembled to date to explore associations between somatic alterations and clinical outcomes in PC. Our results suggest that somatic BRCA2-RB1 codel and MYC amplification define an aggressive subtype of PC with poor clinical outcomes in both gBRCA2 and NC.

Legal entity responsible for the study

Spanish National Cancer Research Centre (CNIO).

Funding

CRIS Foundation, Prostate Cancer Foundation PCF Foundation.

Disclosure

R. Lozano Mejorada: Speaker Bureau/Expert testimony: Roche, Janssen-Cilag, Sanofi; Travel/Accommodation/Expenses: Roche, Janssen-Cilag, Astellas Pharma. E. Castro Marcos: Honoraria (self): Astellas Pharma, AstraZeneca, Bayer, Janssen-Cilag, Pfizer; Advisory/Consultancy: AstraZeneca, Bayer, Janssen; Research grant/Funding (institution): AstraZeneca, Bayer, Janssen; Travel/Accommodation/Expenses: Bayer, Janssen-Cilag, Roche, Astellas Pharma. F. Lopez Campos: Advisory/Consultancy: Astellas Pharma; Speaker Bureau/Expert testimony: Janssen, Astellas Pharma; Travel/Accommodation/Expenses: Astellas Pharma, Janssen; Research grant/Funding (self): Astellas Pharma. U. Anido: Honoraria (self): Pfizer, Novartis, Bayer, Bristol-Myers-Squbb, EUSA Pharma, Eisai, Astellas Pharma, Jassen-Oncology, Sanofi; Advisory/Consultancy: Bayer, Pfizer, Novartis, Ipsen, Eisai, EUSA Pharma, Sanofi; Research grant/Funding (self): Pierre Fabre; Travel/Accommodation/Expenses: Astellas Pharma, Novartis, Roche, Pfizer, Ipsen, Sanofi. M.J. Juan Fita: Advisory/Consultancy: Janssen; Speaker Bureau/Expert testimony: Sanofi, Astellas, Janssen, BMS, Bayer; Travel/Accommodation/Expenses: Janssen. N. Romero Laorden: Research grant/Funding (institution), Travel/Accommodation/Expenses: Janssen; Advisory/Consultancy, Research grant/Funding (institution): Pfizer; Advisory/Consultancy: Janssen, IPSEN, Astellas, Astra-Zeneca, MSD, Bayer, Tesaro, Sanofi. J. Rubio Briones: Advisory/Consultancy: Janssen, Astellas, Bayer; Research grant/Funding (self): HealthMDx. C.C. Pritchard: Advisory/Consultancy: AstraZeneca, Promega. D. Olmos Hidalgo: Honoraria (self): Bayer, Janssen, Sanofi; Advisory/Consultancy: AstraZeneca, Bayer, Clovis Oncology, Daiichi-Sankyo, Janssen, MSD, Roche ; Research grant/Funding (institution): Astellas, AstraZeneca, Bayer, Genentech, Janssen, Medication, MSD, Pfizer, Roche, Tokai Pahrmaceutics; Travel/Accommodation/Expenses: Bayer, Ipsen, Janssen, Roche. All other authors have declared no conflicts of interest.

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Mini Oral - Genitourinary tumours, prostate Mini Oral session

614MO - Cabazitaxel (CBZ) activity in men with metastatic castration resistant prostate cancer (mCRPC) with and without DNA damage repair (DDR) defects

Presentation Number
614MO
Speakers
  • Mihaela Aldea (Villejuif, France)

Abstract

Background

Up to 30% of mCRPC men harbor DDR defects and may benefit from PARP inhibitors (PARPi) after abiraterone/enzalutamide and docetaxel failure. CBZ was recently shown to improve overall survival (OS) in this population, though benefit by DDR status is unknown. We assessed CBZ activity in men with mCRPC according to their DDR status.

Methods

In this retrospective multicenter study, mCRPC patients (pts) who received CBZ were included if their DDR profile from tissue was available. Gene panels included at least BRCA1/2, ATM, CDK12 CHEK1/2, FANCA/FANCL, PALB2, RAD51. DDR positive (DDR+) pts could have had any deleterious germline or somatic DDR. For each DDR+ pts, DDR negative (DDR-) pts were randomly selected after matching for the same molecular test and institution, in a 1:1 ratio. PSA decline, radiological progression-free survival (rPFS) and OS were assessed.

Results

A total of 190 pts were included: 95 DDR+ and 95 DDR-. DDR+ pts were younger than DDR- (66 vs 69 years, p=0.026). The Gleason score was ≥8 in 66% and 55%, metastases (mts) were found at diagnosis in 51% and 41%, respectively. At CBZ start, pts had received a median of 2 prior life-prolonging agents, visceral mts in 24% and 26%, ECOG ≤1 in 78% and 80%, and a median PSA of 91 and 77 ng/ml, respectively. Among DDR+ pts, 40 (42%) had BRCA defects and 43 (45%) received a PARPi. A 50% PSA decline was achieved with CBZ in 29 (32%) and 33 (36%) in DDR+ and DDR- pts (p=0.64). Median rPFS was 5.33 months [95%CI 4.34-7.04] and 5.75 months [95%CI 4.67-7.27] (p=0.55), and median OS was 15.4 months [95%CI 12.16-26.6] and 11.5 months [95%CI 9.76-14.4] (p=0.036), respectively. An ECOG≥2 and visceral mts were independently associated with shorter OS. Outcomes of DDR+ pts are depicted in the Table, according to their sequence with PARPi.

CBZ no PARPi n=53 CBZ before PARPi n=24 CBZ after PARPi n=18
Median prior lines 2 2 3
ECOG ≤1 36/53 (72%) 22/24 (92%) 12/18 (67%)
Visceral mts 13/53 (25%) 5/24 (21%) 4/18 (22%)
50% PSA decline All pts BRCA+ 16/51 (31%) 10/39 (26%) 10/24 (42%) 6/14 (43%) 3/18 (17%) 0/10 (0%)
Median rPFS (months) [95%CI] 6.15 [3.68-8.38] 5.97 [3.98-8.05] 3.09 [0.98-6.57]
Median OS (months) [95%CI] 12.9 [10.2-20] 42.5 [20.2-67.4] 7.2 [5.29-13.41]

Conclusions

CBZ is active in both DDR+ and DDR- mCRPC men. Activity may be lower in pts pre-treated with a PARPi, pending validation.

Legal entity responsible for the study

Karim Fizazi.

Funding

Has not received any funding.

Disclosure

C. Llacer Perez: Travel/Accommodation/Expenses: Astellas Pharma, Angelini Pharma. G. Gravis Mescam: Honoraria (institution): Pfizer, BMS, MSD, AstraZeneca, Astellas, Janssen, Bayer; Advisory/Consultancy: BMS, Pfizer, AstraZeneca, Janssen, Sanofi, Ipsen, Bayer; Travel/Accommodation/Expenses: BMS, Pfizer, AstraZeneca, Janssen, Sanofi, Ipsen, MSD. A. Fléchon: Honoraria (self): AZ Sanofi, Astellas, Janssen AAA; Travel/Accommodation/Expenses: AZ Sanofi, Astellas, Janssen. P. Barthélémy: Honoraria (self): Astellas; Advisory/Consultancy: Janssen-Cilag, Sanofi, MSD, BMS, Pfizer, Novartis, Ipsen, Roche; Travel/Accommodation/Expenses: BMS, Amgen, Pfizer, Janssen-Cilag, Roche, Ipsen. C. Helissey: Advisory/Consultancy: Sanofi, Janssen, Astellas, Roche, AstraZeneca. C. Pobel: Travel/Accommodation/Expenses: Sanofi, Ipsen, Sandoz. E. Castro Marcos: Advisory/Consultancy: AstraZeneca, Bayer, Janssen; Speaker Bureau/Expert testimony: Astellas, AstraZeneca, Bayer, Janssen, Pfizer; Research grant/Funding (institution): AstraZeneca, Bayer, Janssen; Travel/Accommodation/Expenses: AstraZeneca, Bayer, Janssen, Roche. A. Thiery-Vuillemin: Honoraria (self): Pfizer, AstraZeneca, Sanofi, Janssen, Novartis, Ipsen, Roche/Genentech, Bristol-Myers Squibb, MSD, Astellas Pharma; Advisory/Consultancy: Pfizer, AstraZeneca, Sanofi, Janssen, Novartis, Ipsen, Roche, Bristol-Myers Squibb, MSD, Astellas Pharma; Research grant/Funding (institution): Pfizer; Travel/Accommodation/Expenses: Roche, MSD, Janssen, Bristol-Myers Squibb. G. Baciarello: Honoraria (self): Janssen, Roche; Advisory/Consultancy: Amgen, Astellas Oncology, Janssen, Roche; Travel/Accommodation/Expenses: Astellas Oncology, Ipsen, Janssen, Roche. E. Orillard: Honoraria (self): Astellas, Janssen; Travel/Accommodation/Expenses: Pfizer, Amgen. K. Fizazi: Honoraria (self): Astellas Pharma, Bayer, Janssen, Sanofi; Advisory/Consultancy: Amgen (Inst), Astellas Pharma, AstraZeneca (Inst), Bayer, Curevac (Inst), ESSA (Inst), Janssen Oncology, Orion Pharma GmbH, Sanofi; Travel/Accommodation/Expenses: Amgen, Janssen. All other authors have declared no conflicts of interest.

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Mini Oral - Genitourinary tumours, prostate Mini Oral session

LBA22 - Imaging based PCa screening among BRCA mutation carriers: Results from the first round of screening

Presentation Number
LBA22
Speakers
  • David Margel (Petah Tikva, Israel)

Abstract

Background

Male-carriers of BRCA1/2 gene mutations have an increased risk of prostate cancer (PCa) with a more aggressive phenotype. Current screening guidelines suggest the use of PSA only among BRCA2 carriers. Female carriers have extensive guidelines that include imaging. Our objective was to test the prevalence of PCa among BRCA carriers and examine screening strategies, using PSA and multiparametric magnetic resonance imaging (mpMRI).

Methods

We recruited men aged 40–70 with BRCA1/2 germline mutations and no prior history of prostate biopsy. All men underwent an initial round of screening which included PSA, and prostate mpMRI. PSA was considered elevated using an age stratified threshold of ≥1ng/mL for 40-50Y, ≥2ng/mL for 50-60Y, and 2.5ng/mL for 60-70Y. Men with elevated PSA and/or suspicious lesion on mpMRI were offered a biopsy. PSA levels, MRI findings, PCa incidence, and tumor characteristics were evaluated. Decision curve analysis was used to compare screening strategies.

Results

We recruited 188 men (108 BRCA1, 80 BRCA2), mean age 54Y (±9.8). One hundred and ten (57%) had either elevated age-stratified PSA (75; 40%), a suspicious MRI lesion (67; 36%), or both (32; 17%). Of these, 92 (85%) agreed to agreed to a biopsy. Sixteen (8.5%) were diagnosed with PCa; 44% of tumors were classified as intermediate or high risk. mpMRI based screening missed only one of the cancers (6%), while age stratified PSA would have missed five (31%). Decision curve analysis showed that mpMRI screening regardless of PSA had the highest net benefit for PCa diagnosis, especially among men younger than 55Y. We found no difference in the risk of PCa between BRCA1 and BRCA2 (8.3% vs. 8.7%, p=0.91).

Screening Strategy Biopsies avoided n, (%) Cancer detected n, (%) Cancer missed n, (%) Negative predictive value%, (95%CI) Positive predictivevalue%, (95%CI)
PSA>3 67 (73%) 5 (31%) 11 (69%) 83.6% (78.1-87.9) 20% (9.9-36.2)
Elevated Age-stratified PSA 32 (35%) 5 (31%) 11 (69%) 84.4% (71.1-92.2) 18.3% (13.4-24.5)
PI-RADS≥3 29 (32%) 15 (94%) 1 (6%) 96.6% (80.4-99.5) 23.8% (20.2-27.9)
PSA>3 AND PI-RADS≥3 74 (80%) 9 (56%) 7 (44%) 90.6% (84.5-94.4) 50% (32.1-67.9)
Elevated Age-stratified PSA AND PI-RADS≥3 61 (66%) 10 (63%) 6 (27%) 90% (82.5-94.5) 31.3% (21.3-43.3)

Conclusions

PCa is prevalent among BRCA carriers. Age may affect screening strategy for PCa in this population. Young carriers could benefit from initial MRI screening. BRCA carriers older than 55Y should use PSA and referred to mpMRI if elevated.

Clinical trial identification

NCT02053805.

Legal entity responsible for the study

David Margel.

Funding

American Society of Clinical Oncology (ASCO).

Disclosure

D. Margel: Research grant/Funding (self), Career Development Award 2015: ASCO. All other authors have declared no conflicts of interest.

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Mini Oral - Genitourinary tumours, prostate Mini Oral session

Invited Discussant 612MO, 614MO and LBA22

Speakers
  • Eleni Efstathiou (Houston, TX, United States of America)
Mini Oral - Genitourinary tumours, prostate Mini Oral session

615MO - Phase Ib/II study of VERU-111, novel, oral tubulin inhibitor, in men with metastatic castration resistant prostate cancer (mCRPC) who failed an androgen blocking agent

Presentation Number
615MO
Speakers
  • Mark Markowski (Baltimore, MD, United States of America)

Abstract

Background

VERU-111 is an oral, a & b tubulin inhibitor of microtubule polymerization with no affinity for multidrug resistance proteins. A phase 1b/2 clinical study is being conducted to establish the maximum tolerated dose (MTD) and evaluate the preliminary efficacy in men with progressive mCRPC resistant to androgen blocking agents +/- a taxane.

Methods

Phase 1b study was a 3x3 design with escalating oral dosing of 4.5 mg to 81 mg (7 days on drug/14 days off per 21 day cycle). After no dose limiting toxicity was observed, the dose was increased in the next cohort. The schedule was also expanded in those completing the 7 days on/14 days off cycle to continuous dosing/cycle.

Results

30 taxane-naïve mCRPC men with a median age of 76 (61-92) were enrolled. 8 received prior enzalutamide, 12 abiraterone and 10 both. 8 men had bone mets, 5 lymph node, 5 mixed and 1 had soft tissue metastases. The MTD of VERU-111 is 72mg (3 /11 men had Grade 3 diarrhea). No Grade 3 diarrhea was observed at doses <72 mg per day. At doses < 72mg/d, the most common AEs were mild to moderate nausea, vomiting, diarrhea, and fatigue, with no observed neurotoxicity or neutropenia. Antitumor activity was assessed by PSA and bone/CT scans in men that were treated for ≥ 4 continuous 21-day cycles. 5/8 (63%) had PSA declines: 4 (50%) men had ≥ 30% and 2(25%) ≥ 50% declines compared to their 21 day cycle baseline. Based on PCWG3/RECIST 1.1 criteria, objective tumor responses were seen in 2 men (soft tissue and bone) and 5/8 (63%) had stable disease. Objective responses and PSA declines lasted > 12 weeks. Median duration of response has not been reached as 7/8 of the men are still being treated on study with a current duration of 10 months (6-15 months) and three additional men have not yet completed ≥ 4 continuous 21-day cycles.

Conclusions

The phase 1b portion demonstrates that oral VERU-111 has a favorable safety profile allowing for chronic administration and significant/durable antitumor activity. The daily dose of 63mg is being tested in the phase 2 portion. Oral administration, safe long-term treatment and evidence of antitumor activity highlight a potential prominent role of VERU 111 for the treatment of men with mCRPC who failed an androgen blocking agent.

Clinical trial identification

NCT03752099.

Legal entity responsible for the study

Veru Inc.

Funding

Veru Inc.

Disclosure

M. Markowski: Research grant/Funding (institution): Veru Inc. M.A. Eisenberger: Shareholder/Stockholder/Stock options, Officer/Board of Directors: Veru Inc. R. Tutrone: Research grant/Funding (institution): Veru Inc. C. Pieczonka: Research grant/Funding (institution): Veru Inc. R.H. Getzenberg: Leadership role, Shareholder/Stockholder/Stock options, Full/Part-time employment: Veru Inc. D. Rodriguez: Leadership role, Shareholder/Stockholder/Stock options, Full/Part-time employment: Veru Inc. K.G. Barnette: Leadership role, Shareholder/Stockholder/Stock options, Full/Part-time employment, Officer/Board of Directors: Veru Inc. M.S. Steiner: Leadership role, Shareholder/Stockholder/Stock options, Full/Part-time employment, Officer/Board of Directors: Veru Inc. D.R. Saltzstein: Research grant/Funding (institution): Veru Inc. All other authors have declared no conflicts of interest.

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Mini Oral - Genitourinary tumours, prostate Mini Oral session

616MO - Efficacy of BN-brachyury (BNVax) + bintrafusp alfa (BA) + N-803 in castration-resistant prostate cancer (CRPC): Results from a preliminary analysis of the Quick Efficacy Seeking Trial (QuEST1)

Presentation Number
616MO
Speakers
  • Jason M. Redman (Bethesda, United States of America)

Abstract

Background

Immune checkpoint inhibitors have minimal activity in unselected CRPC patients (pts). Combination regimens that generate a tumor-directed immune response (vaccine) and facilitate the resulting anti-tumor immune activity (checkpoint blockade, cytokines) have shown synergy in preclinical models. BNVax is a therapeutic poxviral vaccine targeting brachyury, a transcription factor involved in invasion and metastasis. BA is a bifunctional fusion protein: anti-PD-L1 monoclonal antibody fused to the TGF-β-RII receptor extracellular domain (a TGF-β trap). N-803 is an IL-15 superagonist complex. Here we report an interim efficacy analysis of the QuEST1 study, aimed to rapidly interrogate safety and efficacy of immunotherapy combinations in CRPC.

Methods

Asymptomatic/minimally symptomatic CRPC pts received BNVax + BA (Arm 2.1) or BNVax + BA + N-803 (Arm 2.2). BNVax is given as 2 prime doses followed by boosts. BA 1,200 mg intravenously and N-803 15 μg/kg subcutaneously are given every 2 weeks. Efficacy is defined as objective response by RECIST v1.1 or PSA decrease ≥ 30% sustained for ≥ 21 days. Safety was a secondary endpoint.

Results

As of 4/26/20, 22 CRPC pts enrolled and had 3 to 17 months follow up. 1/13 pts (Arm 2.1) had a PSA response sustained for 13 months. 4/9 (44%) pts (Arm 2.2) had sustained PSA responses; 2 of these pts had confirmed PR, including 1 pt who progressed on abiraterone and enzalutamide. There were no DLTs or grade >3 treatment-related adverse events (TRAEs). Grade 3 TRAEs: 1 pancreatitis (Arm 2.1), 1 secondary adrenal insufficiency (Arm 2.1), and 1 hyperglycemia due to new onset diabetes mellitus (Arm 2.2).

PSA Response/ # Evaluable (%) # with Measurable Disease by RECIST BOR in Pts with Measurable Disease by RECIST
CR PR SD PD
BNVax + BA 1/13 (7.8%) 3 0 0 1 2
BNVax + BA + N-803 4/9 (44%) 3 0 2 1 0

Conclusions

BVax + BA + N-803 demonstrated a manageable safety profile and preliminary evidence of efficacy in CRPC. Addition of N-803 in Arm 2.2 was associated with more activity in this small sample. Arm 2.2 met the predetermined threshold for efficacy and will expand (n=25).

Clinical trial identification

NCT03493945. First posted April 11, 2018.

Editorial acknowledgement

Debra Weingarten, Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute.

Legal entity responsible for the study

Center for Cancer Research, National Cancer Institute.

Funding

The National Cancer Institute, National Institutes of Health has Cooperative Research and Development Agreements (CRADAs) with Bavarian Nordic, Merck KGaA, and ImmunityBio.

Disclosure

All authors have declared no conflicts of interest.

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Mini Oral - Genitourinary tumours, prostate Mini Oral session

Invited Discussant 615MO and 616MO

Speakers
  • Andrea Alimonti (Bellinzona, Switzerland)
Mini Oral - Genitourinary tumours, prostate Mini Oral session

617MO - Repurposing metformin as an anticancer drug: Preliminary results of randomized controlled trial in advanced prostate cancer (MANSMED)

Presentation Number
617MO
Speakers
  • Reham Alghandour (Mansoura, Egypt)

Abstract

Background

There is growing evidence of antineoplastic properties of metformin (MET) in prostate cancer (PCa). Many observational studies suggested that using MET was associated with improvement in overall survival in PCa patients. MET was reported to be associated with reduction of risk of development of castration-resistant state (CRPC). In addition, when MET was combined to ADT or biclutamide, it augmented the antiproliferative effect of these drugs.

Methods

(MANSMED) is a prospective randomized controlled trial. We randomly assigned high risk localized or mHSPC patients to receive standard of care (SOC) (androgen deprivation plus biclutamide 50mg) plus metformin (850 mg twice daily) or SOC alone. Primary end point was time to castrate resistant prostate cancer (CRPC). Secondary endpoint was overall survival (OS) and PSA response rate. The trial was registered at ClinicalTrials.gov ID NCT03137186.

Results

a total of 124 men were randomly allocated into two arms (62 in MET arm, 62 in SOC arm). The baseline demographic and disease characteristics were comparable between two arms. Over a median follow up of 18 months, there were 12 deaths in the MET arm versus 17 deaths in the control arm (P= 0.2). Median time to CRPC was longer in MET arm 29 months (95%CI 25-33) compared to control arm 20 months (95% CI 16-24) (P=0.01). After subgroup analysis, the median time to progression to CRPC was longer at MET arm in high risk localized prostate cancer (P=0.02), in mHSPC patients with low tumor volume was of borderline significance (P= 0.06), and in those with node positive (N1) disease was highly significant (P=0.001). While in patients with high tumor volume, there was no significant difference regarding the median time to CRPC among the two groups (P=0.9). Regarding secondary objective, there was no significant difference between two arms in overall survival (OS) (P= 0.1) or PSA response rate (P=0.5). Notably no significant adverse events were reported in MET arm apart of self-limiting diarrhea.

Conclusions

Metformin potentially lengthen time to CRPC in advanced PCa patients when combined with ADT especially in those with high risk localized PCa, clinically node positive and in those with low tumor volume metastatic hormone naive patients.

Clinical trial identification

NCT03137186.

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.

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Mini Oral - Genitourinary tumours, prostate Mini Oral session

618MO - Local therapy to the primary tumour for newly diagnosed, oligo-metastatic prostate cancer: A prospective randomized, phase II, open-label trial

Presentation Number
618MO
Speakers
  • Bo Dai (Shanghai, China)

Abstract

Background

Oligo-metastatic prostate cancer is recognized as an intermediate stage between localized disease and widespread metastases. The role of radical local therapy (RLT) to the primary tumor for these patients is unclear. We conducted this phase 2 randomized trial to investigate if radical prostatectomy (RP) or prostate radiotherapy (RT) benefits these patients (NCT02742675).

Methods

Oligo-metastases was defined as ≤ 5 bone or extra-pelvic lymph node metastases and no visceral metastases. Patients were randomly assigned (1:1) to receive androgen deprivation therapy (ADT) or ADT plus RLT. For patients allocated to ADT+RLT group, RP was recommended with priority, while RT was administrated to those refused RP and those with unresectable primary tumor after 1-3 months induced ADT. The primary outcome was radiographic progression-free survival (rPFS) and the secondary outcome was overall survival (OS).

Results

A total of 200 patients were enrolled between Sept 1, 2015 and Mar 10, 2019. The median age was 68 years and the median PSA at diagnosis was 98.8 ng/ml. Bone metastases and distant lymph node metastases exited in 96% and 15% of all patients. 96 of 100 patients in ADT+RLT group received RLT including 85 RP and 11 RT. After a median follow-up of 28 months, radiographic progression was observed in 19 of 100 patients in ADT+RLT group and 33 of 100 patients in ADT group. The median rPFS was not reached in ADT+RLT group and 50 months in ADT group (HR = 0.50; 95% CI, 0.28 to 0.87; p = 0.015). RLT related complications occurred in 24 of 85 RP patients (including 3 grade 3-4 complications) and 5 of 11 RT patients. In order to evaluate the OS, longer follow-up period is required.

Conclusions

Local therapy to the primary tumor improves rPFS in patients with newly diagnosed, oligo-metastatic prostate cancer.

Clinical trial identification

NCT02742675.

Legal entity responsible for the study

Bo Dai.

Funding

Fudan University Shanghai Cancer Center.

Disclosure

All authors have declared no conflicts of interest.

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Mini Oral - Genitourinary tumours, prostate Mini Oral session

Invited Discussant 617MO and 618MO

Speakers
  • Noel Clarke (London, United Kingdom)