-Targeted antibody elicits responses in both FGFR3 wild-type
and mutant/fusion patients-
-Favorable tolerability and safety profile and prolonged treatment
duration-
– Results presented at America Society of Oncology (ASCO) Annual
Meeting-
SAN LEANDRO, Calif.–(BUSINESS WIRE)–Rainier Therapeutics, Inc., a privately held clinical stage drug
development company, today announced the first interim analysis results
from its ongoing FIERCE-22 trial of vofatamab in patients with
metastatic bladder cancer. Results were presented at the 2019 American
Society for Clinical Oncology (ASCO) Annual Meeting.
FIERCE-22 is a Phase 1b/2 trial evaluating vofatamab, a FGFR3-targeted
antibody, in combination with pembrolizumab, an immune checkpoint
inhibitor, to determine safety, tolerability and preliminary efficacy in
the treatment of patients with locally advanced or metastatic bladder
cancer who have progressed following platinum-based chemotherapy and who
have not received prior immune checkpoint inhibitor therapy.
The first interim analysis included data from 28 patients enrolled in
the Phase 2 trial, which has a targeted total enrollment of
approximately 74 patients. Results demonstrate that treatment with
vofatamab and pembrolizumab was well tolerated. Five patients
discontinued the study due to treatment emergent adverse events, none
related to vofatamab. No dose reductions of vofatamab occurred.
An overall best response rate of 36 percent (8/22) was observed in
patients with lesions evaluable by RECIST1.1 criteria, 7/22 (32%) were
confirmed. Response rates were similar in both wild type and mutant
fusion patients (33% and 43%, respectively). A majority of patients have
received at least 8 cycles of therapy (1 cycle=21 days). Responses were
notably increased in patients with luminal biology (6 of 9 patients).
Paired biopsy data from this trial were recently presented at AACR
“Frontiers in Bladder Cancer” (see
poster) showing vofatamab induced immune and inflammatory changes in
patients with responses.
“These data provide very encouraging clinical evidence of the effect of
vofatamab, an antibody targeted against both wild type and mutated
FGFR3, in combination with pembrolizumab. Earlier results from this
biopsy-driven trial suggested these responses in the wild type FGFR3
patient cohort occurred in urothelial cancers of luminal subtype which
typically have immunologically cold tumors. Biopsies obtained post
lead-in treatment with vofatamab showed upregulation of genes associated
with an inflammatory response,” said Arlene O. Siefker-Radtke, MD, The
University of Texas MD Anderson Cancer Center. “Further studies are
needed to understand the impact of FGFR3 inhibition in urothelial
cancer.”
“The evidence demonstrated vofatamab provided similar clinical benefits
in these patients regardless of FGFR3 tumor status. We plan to continue
the enrollment of both wild-type and mutant/fusion patients, and to
complete the ongoing Phase 2 trial,” said Esteban Abella, MD, Chief
Medical Officer of Rainier Therapeutics.
In addition, results were presented from the Phase 2 portion of the
FIERCE-21 trial evaluating vofatamab in combination with docetaxel and
vofatamab as monotherapy in patients with locally advanced or metastatic
bladder cancer with FGFR3 mutations or gent fusions who have relapsed
after or are refractory to at least one prior line of chemotherapy. Data
presented indicated vofatamab alone and in combination was well
tolerated, with no observed long-term safety issues. Vofatamab
monotherapy demonstrated single-agent activity in heavily pre-treated
patients. In addition, a substantial portion of patients demonstrated
long-term benefit from monotherapy and combination therapy.
About Vofatamab
Vofatamab (formerly B-701) is an antibody specifically targeted against
the fibroblast growth factor receptor 3 (FGFR3), a known driver of
bladder and potentially other FGFR-driven cancers. Vofatamab is the most
advanced targeted antibody specific for FGFR3 known by Rainier
Therapeutics to be in clinical development. Vofatamab is currently being
evaluated in two clinical trials: FIERCE-22 and FIERCE-21.
About Rainier Therapeutics
Rainier Therapeutics, Inc. is a privately held, clinical stage
biotechnology company developing vofatamab, a targeted antibody for the
potential treatment of metastatic bladder cancer. For more information,
please visit www.rainierrx.com.
Contacts
Julie Rathbun
Rathbun Communications
(206) 769-9291
julie@rathbuncomm.com