CAMBRIDGE, Mass., April 01, 2019 (GLOBE NEWSWIRE) -- Constellation Pharmaceuticals, Inc. (Nasdaq: CNST), a clinical-stage biopharmaceutical company using its expertise in epigenetics to discover and develop novel therapeutics, today presented results from the Phase 1b portion of the ProSTAR clinical trial of CPI-1205 at the American Association for Cancer Research (AACR) annual meeting in Atlanta. Poster CT094/18, ProSTAR: A phase 1b/2 study of CPI-1205, a small molecule inhibitor of EZH2, combined with enzalutamide (E) or abiraterone/prednisone (A/P) in patients with metastatic castration-resistant prostate cancer (mCRPC), was presented at the poster session starting at 1:00 PM EDT today. The Company will present two other posters highlighting its preclinical pipeline later in the AACR meeting.
“We are pleased to report the ProSTAR Phase 1b results,” said Adrian Senderowicz, Chief Medical Officer. “These results show clinical activity in subsets of a heterogeneous population of advanced mCRPC patients in combination with either abiraterone or enzalutamide. Activity was particularly noteworthy in patients taking CPI-1205 in combination with abiraterone, an agent where responses in second-line patients have historically been poor, and in AR-V7-negative patients. Based on the entirety of the results, we initiated the Phase 2 portion of the trial in late 2018 to better define the patient populations most likely to benefit from CPI-1205. We look forward to reporting initial Phase 2 data in the second half of 2019.”
The poster presentation included the following highlights from the Phase 1b portion of ProSTAR, using a February 6, 2019, data cutoff:
|≥80% PSA Reductions in AR-V7-Positive Patients||≥80% PSA Reductions in AR-V7-Negative Patients|
|CPI-1205 + abiraterone**||0/8* (0%)||2/10* (20%)|
|CPI-1205 + enzalutamide**||0/5 (0%)||3/11 (27%)|
|*2 patients not evaluable for PSA response|
|** Includes patients treated with CPI-1205 800 mg three times daily and CPI-1205 400mg twice daily + cobicistat|
|Partial Response||Stable Disease||Disease Control Rate of Any Duration||Disease Control Rate ≥3 Months|
|CPI-1205 + abiraterone||0/8 (0%)||6/8 (75%)||6/8 (75%)||4/8 (50%)|
|CPI-1205 + enzalutamide||1/5 (20%)||2/5 (40%)||3/5 (60%)||3/5 (60%)|
Several patients achieved disease control that exceeded or was approaching six months at the data cutoff while continuing therapy.
For more information on the Phase 1b portion of ProSTAR, please see the poster here.
1 D Khalaf et al., Phase 2 randomized cross-over trial of abiraterone + prednisone (ABI) vs enzalutamide (ENZ) for patients (pts) with metastatic castration resistant prostate cancer (mCRPC): results for 2nd-line therapy, poster presented at 2018 American Society of Clinical Oncology meeting.
Constellation is presenting two additional posters at the American Association for Cancer Research meeting that speak to the depth and breadth of the Company’s product pipeline and its expertise in epigenetics. Poster 4351/11, Single-cell RNA sequencing reveals transcriptomic heterogeneity in response to epigenetic inhibitors, will be presented at the 1PM-5PM EDT poster session on April 2. Poster 4722/12, Efficacy of novel EP300/CBP histone acetyltransferase inhibitor in hormone responsive breast cancer, will be presented at the 8AM-12PM EDT poster session on April 3.
ProSTAR is an open-label Phase 1b/2 clinical trial of CPI-1205, a potent and highly selective small-molecule EZH2 inhibitor, in patients with metastatic castration-resistant prostate cancer (mCRPC) in the second-line setting. The ProSTAR study is evaluating CPI-1205 in combination with either enzalutamide or abiraterone / prednisone (“abiraterone”), which are androgen receptor signaling (ARS) inhibitors, in mCRPC patients who experienced disease progression while receiving the other ARS inhibitor.
Metastatic castration-resistant prostate cancer (mCRPC) is an advanced form of prostate cancer and is defined by disease progression despite treatment with androgen depletion therapy (ADT). mCRPC may present as one or any combination of the following: a continuous rise in serum levels of PSA, progression of known metastases, or appearance of new metastases. Prognosis is associated with several factors, including the ability to perform certain daily activities and the presence of bone pain. Additional symptoms commonly include anemia (low levels of healthy red blood cells), weight loss, fatigue, hypercoagulability (abnormal blood coagulation), and increased susceptibility to infection. mCRPC presents as a spectrum of disease, ranging from patients without symptoms but rising PSA levels despite ADT to patients with metastases and significant debilitation.
About Constellation Pharmaceuticals
Constellation Pharmaceuticals is a clinical-stage biopharmaceutical company developing novel therapeutics that selectively modulate gene expression to address serious unmet medical needs in patients with cancer. The Company has a deep understanding of how epigenetic and chromatin modifications in cancer cells and in the tumor and immune microenvironment play a fundamental role in driving disease progression and drug resistance. Constellation is driving development of the EZH2 inhibitors CPI-1205 and CPI-0209 for the treatment of metastatic castration-resistant prostate cancer and other cancers as well as the BET inhibitor CPI-0610 for the treatment of myelofibrosis. The Company is also applying its broad research and development capabilities to explore other novel targets that directly and indirectly impact gene expression to fuel a sustainable pipeline of innovative small-molecule product candidates.
This press release contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995 that involve substantial risks and uncertainties, including statements regarding the implications of preliminary clinical data, the development status of the Company’s product candidates, the Company’s plans for future data presentations, its anticipated achievement of milestones, including determination of proof of concept and its financial guidance regarding the period in which it will have capital available to fund its operations. All statements, other than statements of historical facts, contained in this press release, including statements regarding the Company’s strategy, future operations, future financial position, prospects, plans and objectives of management, are forward-looking statements. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements are based on management’s current expectations of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially and adversely from those set forth in, or implied by, such forward-looking statements. These risks and uncertainties include, but are not limited to, risks associated with Constellation’s ability to: obtain and maintain necessary approvals from the FDA and other regulatory authorities; continue to advance its product candidates in clinical trials; whether preliminary or interim results from a clinical trial will be predictive of the final results of the trial; replicate in later clinical trials positive results found in preclinical studies and early-stage clinical trials of CPI-1205, CPI-0610 and its other product candidates; advance the development of its product candidates under the timelines it anticipates, or at all, in current and future clinical trials; obtain, maintain or protect intellectual property rights related to its product candidates; manage expenses; and raise the substantial additional capital needed to achieve its business objectives. For a discussion of other risks and uncertainties, any of which could cause the Company’s actual results to differ from those contained in the forward-looking statements, see the “Risk Factors” section, as well as discussions of potential risks, uncertainties, and other important factors, in the Company’s most recent filings with the Securities and Exchange Commission. In addition, the forward- looking statements included in this press release represent the Company’s views as of the date hereof and should not be relied upon as representing the Company’s views as of any date subsequent to the date hereof. The Company anticipates that subsequent events and developments will cause the Company’s views to change. However, while the Company may elect to update these forward-looking statements at some point in the future, the Company specifically disclaims any obligation to do so. CPI-1205, CPI-0610, CPI-0209, and other product candidates are investigational in nature and have not yet been approved by the FDA or other regulatory authorities.
Senior Director, Investor Relations
MacDougall Biomedical Communications