Abstract 5692
Background
FPA150 is a fully human antibody against B7-H4 (a transmembrane protein of the B7 family) blocking negative regulatory function in T cells. FPA150 additionally exhibits enhanced antibody-dependent cell-mediated cytotoxicity and in vivo synergizes with anti-PD1 agents. We initiated a phase Ia/Ib evaluation of safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD) and activity in monotherapy (mono) and with anti-PD1 (combo). A current update of this ongoing trial is provided.
Methods
Trial design (see table)Table:
1198P
Phase | Patients | Design | Doses | Objective | Status |
---|---|---|---|---|---|
1a | |||||
Dose Escalation | Advanced solid tumors | Accelerated Titration; 3 + 3 escalation | 0.01-0.3 mg/kg; 1-20 mg/kg | Safety, tolerability & PK | Complete; recommended dose (RD) identified |
Dose Exploration | B7-H4 + solid tumors | Pre- and on-treatment biopsies (Bx) | 3 mg/kg; 10 mg/kg | Safety, tolerability, PK & PD | Ongoing |
1a Combo Safety Lead-In | B7-H4+ ovarian cancer | 3 + 3 De-escalation | FPA150 at RD & 200 mg pembrolizumab (pembro) | Safety, tolerability, PK & RD FPA150 | Ongoing |
1b | |||||
3 Mono cohorts | B7-H4+ breast, ovarian & endometrial | Dose Expansion (Bx) | 20 mg/kg | Safety, tolerability, PD & efficacy | Ongoing |
1C1 Combo | B7-H4+ ovarian cancer | Dose Expansion (Bx) | 200 mg pembro & RD FPA150 | Safety, tolerability, PD & efficacy | Not yet started |
Results
At 3/15/2019 data snapshot, 29 pts with solid tumors (12 ovarian, 7 GI, 3 GYN, 3 head/neck, 2 GU, and 2 other) received FPA150 in dose escalation (n = 21) and dose exploration (n = 8). FPA150 demonstrated ∼ dose-proportional exposure at doses ≥0.3 mg/kg and half-life of 1-2 weeks. To date, no dose-limiting toxicities, treatment-related serious adverse events or treatment-related adverse events (TRAEs) leading to drug discontinuation have been identified (1 Grade 3 TRAE of decreased lymphocyte count); others were Grade 1-2, with most common being diarrhea (16.7%), and fatigue (13.8%). Enrollment to phase Ib mono and phase Ia combo is ongoing. Expanded safety, PD and activity from phase Ib mono and phase Ia combo will be presented.
Conclusions
FPA150 RD for phase Ib mono identified as 20 mg/kg (Sachdev, ASCO 2019). Mono appears well tolerated during dose escalation/exploration allowing evaluation in combination therapy. Sachdev, J et al. Phase Ia/1b study of first-in-class B7-H4 antibody, FPA150, as monotherapy in patients with advanced solid tumors. Proc Am. Soc. Clin. Oncol 2019.
Clinical trial identification
NCT03514121.
Editorial acknowledgement
Legal entity responsible for the study
Five Prime Therapeutics, Inc.
Funding
Five Prime Therapeutics, Inc.
Disclosure
Z.A. Wainberg: Advisory / Consultancy: Bristol Meier Squibb; Advisory / Consultancy: Five Prime Therapeutics; Advisory / Consultancy: Merck; Advisory / Consultancy: Eli Lilly; Advisory / Consultancy: Novartis; Advisory / Consultancy: Bayer. J.C. Sachdev: Honoraria (self): Celgene; Honoraria (self): Novartis; Honoraria (self): Puma Technology; Honoraria (self): Tempus; Honoraria (self): Ipsen; Advisory / Consultancy: Celgene; Research grant / Funding (institution): Celgene; Travel / Accommodation / Expenses: Celgene; Advisory / Consultancy: Five Prime Therapeutics. T. Bauer: Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses, institution: Ignyta; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Guardant Health; Advisory / Consultancy, Research grant / Funding (institution): Loxo; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution), Self and institution: Pfizer; Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Moderna Therapeutics; Speaker Bureau / Expert testimony, Research grant / Funding (institution): Bayer; Research grant / Funding (institution): Daiichi Sankyo; Research grant / Funding (institution): Medpacto; Research grant / Funding (institution): Incyte; Research grant / Funding (institution): Mirati Therapeutics; Research grant / Funding (institution): MedImmune; Research grant / Funding (institution): AbbVie; Research grant / Funding (institution): AstraZeneca; Research grant / Funding (institution): MabVax; Research grant / Funding (institution): Stemline Therapeutics; Research grant / Funding (institution): Merck; Research grant / Funding (institution): Eli Lilly; Research grant / Funding (institution): Glaxo Smith Kline; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): Immunogen; Research grant / Funding (institution): Deciphera; Research grant / Funding (institution): Merimack; Research grant / Funding (institution): Immunogen. S. Pant: Advisory / Consultancy: Mirati Therapeutics; Advisory / Consultancy: Eli Lilly; Advisory / Consultancy: Red hill Biopharma Ltd; Advisory / Consultancy: Xencor; Advisory / Consultancy: Five Prime Therapeutics; Advisory / Consultancy: Novartis; Advisory / Consultancy: Rgenix; Advisory / Consultancy: Sanofi-Aventis; Advisory / Consultancy: Arqule; Advisory / Consultancy: Bristol-Myers Squibb; Advisory / Consultancy: Onco Response; Advisory / Consultancy: Sanofi US Services Inc; Advisory / Consultancy: GlaxoSmith Kline; Speaker Bureau / Expert testimony: Tyme, Inc; Speaker Bureau / Expert testimony: 4-D Pharma. S. Chawla: Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Amgen; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Roche; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: GlaxoSmithKline; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Threshold Pharmaceuticals; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: CytRx; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Ignyta; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Immune Design; Honoraria (self), Speaker Bureau / Expert testimony: TRACON Pharma; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Karyopharm Therapeutics; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Sarcoma Alliance for REsearch Through Collaboration; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Janssen. N. Marina: Full / Part-time employment: Five Prime Therapeutics. H. Xiang: Full / Part-time employment: Five Prime Therapeutics. W. Deng: Full / Part-time employment: Five Prime Therapeutics. M. Schmidt: Full / Part-time employment: Five Prime Therapeutics. A. Patnaik: Advisory / Consultancy: Bayer; Advisory / Consultancy: Novartis; Advisory / Consultancy: Genentech; Advisory / Consultancy, Research grant / Funding (institution): Merck; Advisory / Consultancy: Seattle Genetics; Advisory / Consultancy: Bristo-Myers Squibb; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Eli Lilly; Research grant / Funding (institution): Plexxikon; Research grant / Funding (institution): Corvus Pharmaceuticals; Research grant / Funding (institution): Tesaro; Research grant / Funding (institution): Forty-seven; Research grant / Funding (institution): Five Prime Therapeutics; Research grant / Funding (institution): Infinity Pharmaceuticals; Research grant / Funding (institution): Proximagen; Research grant / Funding (institution): Pieris; Research grant / Funding (institution): Surface Oncology; Research grant / Funding (institution): Livson; Research grant / Funding (institution): Vigeo Therapeutics; Research grant / Funding (institution): Astella Pharma. P. LoRusso: Advisory / Consultancy: AbbVie; Advisory / Consultancy: Agios; Advisory / Consultancy: Alexion; Advisory / Consultancy: Ariad; Advisory / Consultancy: Five Prime Therapeutics; Advisory / Consultancy: GenMab; Advisory / Consultancy: Glenmark; Advisory / Consultancy: Halozyme; Advisory / Consultancy: Menarini; Advisory / Consultancy: Novartis; Advisory / Consultancy: Roche-Genentech; Advisory / Consultancy: Genentech; Advisory / Consultancy: CytomX; Advisory / Consultancy: Omniox; Advisory / Consultancy: Ignyta; Advisory / Consultancy: Takeda; Advisory / Consultancy: SOTIO; Advisory / Consultancy: Cybrexa; Advisory / Consultancy: Agenus; Advisory / Consultancy: Tyme.
Resources from the same session
3489 - Overall Survival (OS) and Metastasis-Free Survival (MFS) in men with Biochemically Relapsed (BCR) Prostate Cancer after radical prostatectomy (RP) managed with deferred Androgen Deprivation Treatment (ADT): A combined Johns Hopkins and CPDR study
Presenter: Catherine Marshall
Session: Poster Display session 3
Resources:
Abstract
4606 - ARCHES – the role of androgen deprivation therapy (ADT) with enzalutamide (ENZA) or placebo (PBO) in metastatic hormone-sensitive prostate cancer (mHSPC): Post hoc analyses of high and low disease volume and risk groups
Presenter: Arnulf Stenzl
Session: Poster Display session 3
Resources:
Abstract
2975 - Updated survival analyses of a multicentric phase II randomized trial of docetaxel (D) plus enzalutamide (E) versus docetaxel (D) as first line chemotherapy for patients (pts) with metastatic castration-resistant prostate cancer (mCRPC) (CHEIRON study).
Presenter: Orazio Caffo
Session: Poster Display session 3
Resources:
Abstract
2708 - Real-world analysis of patients (pts) with metastatic castration-resistant prostate cancer (mCRPC) receiving vs not receiving chemotherapy in the treatment sequence
Presenter: Alicia Morgans
Session: Poster Display session 3
Resources:
Abstract
2134 - Baseline fracture risk in men with prostate cancer starting the STAMPEDE trial
Presenter: Janet Brown
Session: Poster Display session 3
Resources:
Abstract
3504 - Risk of falls and fractures in patients with castration resistant prostate cancer (CRPC) treated with new hormonal agents – a meta-analysis of randomized controlled trials.
Presenter: Rodrigo Coutinho Mariano
Session: Poster Display session 3
Resources:
Abstract
2342 - Pain progression at initiation of chemotherapy in metastatic Castration-Resistant Prostate Cancer (mCRPC) is associated with a poor prognosis: a post-hoc analysis of FIRSTANA
Presenter: Nicolas Delanoy
Session: Poster Display session 3
Resources:
Abstract
5331 - Pain evaluation in patients (pts) with metastatic castration-resistant prostate cancer (mCRPC) treated with radium-223 (Ra-223) in the PARABO observation study
Presenter: Holger Palmedo
Session: Poster Display session 3
Resources:
Abstract
2823 - Time to castration resistant prostate cancer (CRPC) and the risk of developing immune disorders
Presenter: Vincenza Conteduca
Session: Poster Display session 3
Resources:
Abstract
1500 - Retrospective evaluation of neutropenic admission events in metastatic or high-risk hormone-sensitive prostate cancer (HSPC) patients having docetaxel chemotherapy upfront or for castrate-resistant prostate cancer (CRPC) in STAMPEDE
Presenter: Harriet Mintz
Session: Poster Display session 3
Resources:
Abstract