On June 1, 2019 Blueprint Medicines Corporation (NASDAQ: BPMC), a precision therapy company focused on genomically defined cancers, rare diseases and cancer immunotherapy, reported data from the registration-enabling NAVIGATOR trial of avapritinib in patients with PDGFRA Exon 18 mutant gastrointestinal stromal tumors (GIST) and fourth-line GIST (Press release, Blueprint Medicines, JUN 1, 2019, View Source [SID1234536767]). These results were presented at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) 2019 Annual Meeting and will form the basis for planned worldwide marketing applications for avapritinib, an investigational, highly selective KIT and PDGFRA inhibitor for patients with advanced GIST. The data demonstrate clinical activity and favorable tolerability in patients with PDGFRA Exon 18 mutant and fourth-line GIST, two populations with no effective therapies.

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

Data from the ongoing NAVIGATOR trial in patients with PDGFRA Exon 18 mutant GIST, which primarily includes the D842V mutation, and fourth-line GIST support Blueprint Medicines’ plans to submit a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) in June 2019 and a Marketing Authorization Application (MAA) to the European Medicines Agency (EMA) in the third quarter of 2019. Avapritinib has received FDA Breakthrough Therapy Designation for the treatment of patients with unresectable or metastatic GIST harboring the PDGFRα D842V mutation.

In patients with PDGFRA Exon 18 mutant GIST, the objective response rate (ORR) was 86 percent and the median duration of response (DOR) was not reached. In patients with fourth-line GIST, the ORR was 22 percent and the median DOR was 10.2 months. ORR and DOR per central radiographic review will be the primary registrational endpoints. Avapritinib was well-tolerated with most adverse events (AEs) reported by investigators as Grade 1 or 2. These results were as of a data cutoff date of November 16, 2018.

"These data highlight the potential of avapritinib to shift the treatment paradigm for GIST toward a precision medicine approach based on the genomic driver of disease," said Michael Heinrich, M.D., Professor of Medicine at Oregon Health & Science University and an investigator on the NAVIGATOR trial. "In the PDGFRα D842V population where we currently have no effective agents, avapritinib demonstrated remarkable activity regardless of line of therapy. I believe these results will further catalyze the use of mutational testing in GIST patients prior to starting therapy, which is currently recommended by treatment guidelines. Importantly, avapritinib has also demonstrated the potential to suppress complex and heterogenous mutational profiles associated with treatment-resistant fourth-line GIST. Combined with the well-tolerated safety profile of avapritinib, I believe these data show the broad potential of avapritinib to advance care across the GIST treatment landscape."

"These results further demonstrate the activity and favorable tolerability of avapritinib, a potent and highly selective PDGFRA and KIT inhibitor, in two patient populations with tumor mutations resistant to currently available therapies," said Andy Boral, M.D., Ph.D., Chief Medical Officer at Blueprint Medicines. "Based on the strength of these data and the clear medical needs in PDGFRA Exon 18 mutant and fourth-line GIST, we look forward to working closely with global regulatory authorities to bring this important advance in treatment to patients as expeditiously as possible. In addition, the previously reported preliminary data in third-line and second-line GIST support our broad clinical development program and highlight the potential of avapritinib to become a foundational GIST treatment."

Highlights from ASCO (Free ASCO Whitepaper) Presentation of NAVIGATOR Trial Data

As of the data cutoff date of November 16, 2018, 204 patients were treated with avapritinib at a starting dose of 300 or 400 mg once daily (QD). Patients with PDGFRA Exon 18 mutant GIST were treated across all lines of therapy. Patients with fourth-line or later GIST had a median of four prior lines of therapy (ranging from three to 11) prior to receiving avapritinib.

Clinical Activity Data

As of the data cutoff date, 43 patients with PDGFRA Exon 18 mutant GIST (including 38 patients with PDGFRα D842V-driven GIST) and 111 patients with fourth-line GIST were treated at a starting dose of 300 or 400 mg QD and evaluable for response assessments. Patients were evaluable if they had at least one centrally reviewed radiographic scan, and data are based on modified Response Evaluation Criteria in Solid Tumors version 1.1 (mRECIST 1.1 criteria) for GIST.

In evaluable patients with PDGFRA Exon 18 mutant GIST:

The ORR was 86 percent, with three confirmed complete responses (CR) and 34 partial responses (PR; one pending confirmation1).
The ORR was 100 percent (two CRs and three PRs; all responses were confirmed) in the first-line treatment setting.
The median DOR was not reached.
28 patients (78 percent) remained in response as of the data cutoff date.
Median follow-up was 10.9 months.
In evaluable patients with fourth-line GIST:

The ORR was 22 percent, with one confirmed CR and 23 PRs (one pending confirmation1).
The median DOR was 10.2 months.
Median follow-up was 10.8 months.
Safety Data

Avapritinib had a favorable safety profile in patients treated at a starting dose of 300 or 400 mg QD, with most AEs determined by investigators to be Grade 1 or 2 as of the data cutoff date. Across all patients, 8 percent of patients discontinued treatment with avapritinib due to treatment-related AEs. A lower incidence of commonly reported AEs was reported at 300 mg QD dosing compared to 400 mg QD dosing.

Across all grades, the most common treatment-emergent AEs (regardless of relationship to avapritinib) reported by investigators (≥25 percent) were nausea, fatigue, anemia, cognitive effects, periorbital edema, vomiting, decreased appetite, diarrhea, increased lacrimation and peripheral edema. Investigator-reported Grade 3 or 4 treatment-related AEs (≥2 percent) included anemia, fatigue, cognitive effects, increased blood bilirubin, diarrhea, hypophosphatemia, decreased neutrophil count, neutropenia and lymphopenia.

These data on avapritinib were presented at the ASCO (Free ASCO Whitepaper) 2019 Annual Meeting in a poster presentation on Saturday, June 1 (Abstract Number: 11022). A copy of the poster is available in the "Science—Publications and Presentations" section of Blueprint Medicines’ website at www.BlueprintMedicines.com.

About the Avapritinib Clinical Development Program in GIST

Blueprint Medicines is pursuing a broad clinical development program for avapritinib across all lines of GIST. Avapritinib is currently being evaluated in two global registration-enabling clinical trials for GIST: the Phase 1 NAVIGATOR trial and the Phase 3 VOYAGER trial.

The NAVIGATOR trial is designed to evaluate the safety, tolerability and clinical activity of avapritinib in patients with unresectable or metastatic GIST. The trial consists of two parts, a dose escalation portion and an expansion portion. Trial objectives include assessing response using blinded central radiology review, as well as pharmacokinetics and pharmacodynamic measures. The expansion cohorts of the trial enrolled patients at multiple sites in the United States, European Union and Asia.

The VOYAGER trial is a global, open-label, randomized, Phase 3 trial designed to evaluate the safety and efficacy of avapritinib versus regorafenib in patients with third- or fourth-line GIST. The trial is designed to enroll approximately 460 patients randomized 1:1 to receive either avapritinib or regorafenib at multiple sites in the United States, Canada, European Union, Australia and Asia.

In the second half of 2019, Blueprint Medicines plans to initiate COMPASS-2L, a global, randomized, Phase 3 precision medicine trial. The trial will evaluate the safety and efficacy of avapritinib versus sunitinib in second-line GIST patients with pre-specified disease genotypes.

Patients and physicians interested in the Phase 3 VOYAGER trial can contact the Blueprint Medicines study director at [email protected] or 1-617-714-6707. For more information about the VOYAGER trial, please visit www.BlueprintClinicalTrials.com/VOYAGER. Additional details are available on www.clinicaltrials.gov (ClinicalTrials.gov Identifier: NCT03465722).

About GIST

GIST is a sarcoma, or tumor of bone or connective tissue, of the gastrointestinal (GI) tract. Tumors arise from cells in the wall of the GI tract and occur most often in the stomach or small intestine. Most patients are diagnosed between the ages of 50 to 80, and diagnosis is typically triggered by GI bleeding, incidental findings during surgery or imaging and, in rare cases, tumor rupture or GI obstruction.

Most GIST cases are caused by a spectrum of clinically relevant mutations that force the KIT or PDGFRA protein kinases into an increasingly active state. Because currently available therapies primarily bind to the inactive protein conformations, certain primary and secondary mutations typically lead to treatment resistance and disease progression.

Treatment options for KIT-driven GIST patients who progress beyond imatinib are currently limited. There are no effective treatment options for patients with metastatic PDGFRα D842V-driven GIST, and progression occurs in a median of approximately three to four months with available therapy. In unresectable or metastatic GIST, clinical benefits from existing treatments can vary by mutation type. Mutational testing is critical to tailor therapy to the underlying disease driver and is recommended in expert guidelines.

About Avapritinib

Avapritinib is an investigational, oral precision therapy that selectively and potently inhibits KIT and PDGFRA mutant kinases. It is a type 1 inhibitor designed to target the active kinase conformation; all oncogenic kinases signal via this conformation. Avapritinib has demonstrated broad inhibition of KIT and PDGFRA mutations associated with GIST, including potent activity against activation loop mutations that are associated with resistance to currently approved therapies. In contrast to approved multi-kinase inhibitors, avapritinib has shown marked selectivity for KIT and PDGFRA over other kinases. In addition, avapritinib is uniquely designed to selectively bind and inhibit D816V mutant KIT, the common driver of disease in approximately 95 percent of all systemic mastocytosis (SM) patients. Preclinical studies have shown avapritinib potently inhibited KIT D816V at sub-nanomolar potencies with minimal off-target activity.

Blueprint Medicines is initially developing avapritinib for the treatment of advanced GIST, advanced SM, and indolent and smoldering SM. The FDA has granted avapritinib two Breakthrough Therapy Designations, one for the treatment of unresectable or metastatic GIST harboring the PDGFRα D842V mutation and one for the treatment of advanced SM, including the subtypes of aggressive SM, SM with an associated hematologic neoplasm and mast cell leukemia.

Blueprint Medicines has an exclusive collaboration and license agreement with CStone Pharmaceuticals for the development and commercialization of avapritinib and certain other drug candidates in Mainland China, Hong Kong, Macau and Taiwan. Blueprint Medicines retains development and commercial rights for avapritinib in the rest of the world.

On June 1, 2019 Veracyte, Inc. (Nasdaq: VCYT) reported new data demonstrating the potential for its Afirma Xpression Atlas (XA) genomic test to guide targeted treatment selection for patients with a rare but aggressive form of thyroid cancer concurrent with diagnosis by the company’s Afirma Genomic Sequencing Classifier (GSC) (Press release, Veracyte, JUN 1, 2019, View Source [SID1234536766]).

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

The findings advance physicians’ ability to answer multiple clinical questions for their thyroid patients using a single, minimally invasive sample. They were presented today at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting, which is being held May 31-June 4, 2019 in Chicago.

Researchers used the Afirma XA to conduct RNA sequencing on 90 thyroid fine needle aspiration samples that had been diagnosed with medullary thyroid cancer (MTC) through the Afirma GSC. The cohort was derived from nearly 30,000 sequential samples that were indeterminate or suspicious for cancer following traditional cytopathology testing. The researchers found that the Afirma XA identified a gene variant or fusion in 74 percent of the MTC cases and that 99 percent of these cases had one or more variants or fusions – RET, KRAS, HRAS and/or BRAF alterations – that are targeted by new therapies that are currently in clinical trials or early stage development.

"With the emergence of new molecularly targeted therapies for medullary thyroid cancer, molecular testing to identify the driver genomic mutations will be key to optimizing patient outcomes," said Lori J. Wirth, M.D., medical director of the Center for Head and Neck Cancers at Massachusetts General Hospital, who presented the findings in a poster session today. "The potential to select targeted therapy at the time of diagnosis may be especially helpful for patients with advanced disease."

The Afirma GSC and Xpression Atlas provide physicians with a comprehensive solution for a complex landscape in thyroid nodule diagnosis and individualization of care. Veracyte developed the Afirma GSC with RNA whole-transcriptome sequencing and machine learning. The test helps identify patients with benign thyroid nodules among those with indeterminate cytopathology results in order to help patients avoid unnecessary diagnostic thyroid surgery, while also identifying patients with MTC. The Afirma XA provides physicians with genomic alteration content from the same fine needle aspiration samples that are used in Afirma GSC testing and may help physicians decide with greater confidence on the surgical or therapeutic pathway for their patients. The Afirma XA includes 761 DNA variants and 130 RNA fusion partners in over 500 genes that are associated with thyroid cancer.

"These new data show that our comprehensive Afirma solution can not only help patients avoid unnecessary diagnostic surgery when their nodules are benign, but may also inform targeted therapy selection when thyroid cancer is diagnosed," said Bonnie Anderson, Veracyte’s chairman and chief executive officer. "These findings represent a significant step forward in delivering on the promise of precision medicine for thyroid cancer patients."

About Thyroid Cancer

The American Cancer Society estimates that 54,070 people in the United States will be diagnosed with thyroid cancer this year. Medullary thyroid cancer, which is more difficult to find and treat, makes up approximately 4 percent of all thyroid cancers. Each year in the United States approximately 525,000 patients undergo FNA biopsies to evaluate thyroid nodules for cancer. Up to 30 percent of these patients receive indeterminate results – meaning they are not clearly benign or malignant – and, historically, most were directed to diagnostic surgery even though 70 percent to 80 percent of the time the nodules ultimately proved to be benign.

On June 1, 2019 Sierra Oncology, Inc. (SRRA), a late-stage drug development company focused on advancing targeted therapeutics for the treatment of patients with significant unmet needs in hematology and oncology, reported positive preliminary clinical data from its two first-in-human Phase 1/2 studies of SRA737, a highly selective oral Chk1 inhibitor, as monotherapy and as SRA737+LDG (SRA737 potentiated by low dose gemcitabine), at the 2019 Annual Meeting of the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) in Chicago (Press release, Sierra Oncology, JUN 1, 2019, View Source [SID1234536764]). Anti-cancer activity was demonstrated across multiple indications and genetic contexts, with SRA737+LDG specifically achieving a notable 30% response rate in anogenital cancer patients.

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

"In collaboration with Dr. Udai Banerji, Chief Investigator, The Institute of Cancer Research (ICR) and The Royal Marsden NHS Foundation Trust, we have established proof-of-concept clinical data for SRA737 and identified a potential clinical indication that could be pursued towards registration," said Dr. Nick Glover, President and CEO of Sierra Oncology. "Our strategy has been to execute a cutting-edge signal-seeking survey of a broad cancer landscape, across both a range of indications and a spectrum of genetic contexts associated with replication stress (RS). The resulting clinical data demonstrate that SRA737 has demonstrable anti-cancer activity in multiple indications, in particular in combination with LDG, and has a favorable tolerability profile, opening up several attractive development paths forward for this unique drug candidate. Of note, we have recently received management support from a major immuno-oncology company to potentially supply their leading immunotherapeutic agent to run a combination study with SRA737. We will further analyze these opportunities and evaluate next steps with this asset over the coming months, exploring options to enable the continued advancement of SRA737 in the context of our emerging pipeline."

"These clinical data provide clear evidence of anti-tumor activity with SRA737+LDG and demonstrate that the combination is well tolerated. Of particular note were the promising responses we observed in squamous cell anogenital/cervical cancers in previously treated patients with advanced disease," said Dr. Rebecca Kristeleit, Clinical Senior Lecturer and Honorary Consultant Medical Oncologist at University College London (UCL) Cancer Institute & UCLH Dept. of Oncology. "In my opinion, SRA737+LDG warrants additional registration-intent clinical development focused on patients with anogenital cancer, an indication for which the second line metastatic setting represents a significant unmet medical need with no approved therapies and very poor life expectancy."

"We are pleased that these signal-generating studies provided compelling support for our original hypothesis that SRA737’s anti-cancer activity was correlated with specific genetic contexts. Indeed, our clinical data demonstrate that anogenital cancer represents a synthesis of overlapping replication stress genetics, providing particular sensitivity to SRA737+LDG. Moreover, these findings support that low dose gemcitabine acts as an exogenous driver of RS that further potentiates SRA737’s anti-cancer activity," said Dr. Christian Hassig, Chief Scientific Officer, Sierra Oncology. "From a safety perspective, our data support that SRA737 and SRA737+LDG are conducive to development in combination with other therapeutic approaches, providing paths for further development with PARP inhibitors and with immunotherapy, combinations for which we have previously reported robust synergistic preclinical efficacy."

The company will be hosting an Analyst and Investor Event on Monday June 3, 2019, to discuss these clinical findings and potential next steps in the development strategy for SRA737+LDG. The event will feature presentations by distinguished oncologists Professor Johann de Bono and Dr. Rebecca Kristeleit.

SRA737+LDG (SRA737-02) First-in-Human Phase 1/2 Preliminary Results
This signal-seeking Phase 1/2 study (NCT02797977) was designed to investigate the safety and tolerability of SRA737 in combination with sub-therapeutic, low dose gemcitabine (LDG), as well as to evaluate preliminary anti-tumor activity of SRA737 potentiated by LDG in tumors with genetic alterations predicted to confer increased intrinsic RS and Chk1i sensitivity. Relative to standard-of-care, gemcitabine doses tested were approximately 10-25% of a standard chemotherapeutic dose.

Preliminary Efficacy Results (Evaluable Patients):

Striking anti-tumor activity was observed in subjects with advanced anogenital cancer (Overall Response Rate (ORR) = 30%; Disease Control Rate (DCR) = 60%), encompassing noteworthy tumor decreases (e.g. -66% tumor decrease; resolution of pleural effusion) and promising durations of treatment (e.g. ~11 months).
Overall, Partial Responses were observed in six subjects and 41 subjects had a best response of Stable Disease (SD); durable SD lasting ≥ 4 months was recorded in 32 subjects and was observed in all expansion cohorts.
The combination of SRA737+LDG was generally well tolerated. There was no evidence of emergent or cumulative toxicity and/or declining tolerability with up to 13 cycles of treatment. At the time of the data cut off (May 3, 2019), 22 subjects remained on study treatment.
Based on overall tolerability, the recommended Phase 2 dose is 500 mg SRA737 + 250 mg/m2 LDG.
Genetic Analyses:

Preliminary evidence suggests several intrinsic sources of RS combined with LDG significantly enhance Chk1 activity.
FA/BRCA gene network mutations were associated with the most favorable outcomes in this study (ORR = 25%; DCR = 81%). The FA/BRCA gene network encodes a series of Fanconi Anemia and other proteins involved directly or indirectly in replication fork metabolism and management of RS.
Mutations in the PI3K gene network correlated with robust DCR (75%) and tumor responses in two subjects, consistent with previous reports of Chk1i sensitivity associated with PIK3CA mutations.
A preliminary correlation of noteworthy tumor responses with elevated tumor mutational burden (TMB) was also observed, particularly in the anogenital cohort (three of four TMB patients achieved notable tumor decreases). Elevated TMB is consistent with increased genomic instability and represents a possible future enrichment strategy.
SRA737-01 Monotherapy First-in-Human Phase 1/2 Preliminary Results
This signal-seeking Phase 1/2 study (NCT02797964) was designed to investigate the safety and tolerability of continuous, oral daily dosing of SRA737, as well as to survey a broad range of cancer indications and genetic contexts in the expansion phase, in order to evaluate preliminary anti-tumor activity and delineate potential genetic signatures and/or tumor indications that might warrant additional therapeutic investigation.

Preliminary Efficacy Results (Evaluable Patients):

The maximum tolerated dose was 1000 mg per day, and based on overall tolerability and PK, the recommended monotherapy dose is 800 mg per day, highlighting the tolerability of SRA737.
Evidence of anti-tumor activity was observed in subjects with HGSOC, colorectal, prostate and non-small cell lung cancer; no RECIST PRs or CRs were confirmed, but several noteworthy tumor reductions were recorded.
HGSOC appeared as the most sensitive tumor to SRA737 monotherapy in the SRA737-01 study. Although heavily pre-treated (~5 prior lines), the HGSOC cohort demonstrated directionally favorable disease control (DCR = 54%) with notable maximal tumor reductions of 29% and 27% in two patients.
A best overall response of stable disease (SD) was seen in 34 (32%) subjects. At the time of the data cut off, durable SD lasting ≥ 4 months was recorded in 22 (21%) subjects and was observed in all Cohort Expansion phase tumor types except head and neck cancer.
Genetic Analyses:

Subjects whose tumors harbored FA/BRCA network mutations, regardless of indication, displayed favorable outcomes (DCR = 71%; DOS = 3.8 cycles), consistent with similar observations in subjects treated with SRA737+LDG.
Within the FA/BRCA pathway, several notable tumor decreases occurred in subjects harboring two genetic alterations, such as a DDR checkpoint kinase gene or within the PI3K network. This phenomenon was also observed in the SRA737+LDG clinical study.
Alterations in the PI3K gene network (PIK3CA, AKT, PTEN) were associated with a 77% DCR.
No clear trend toward enhanced sensitivity was noted with CCNE1 gene amplification, although the small subset of subjects enrolled with unambiguous CCNE1 amplifications renders definitive conclusions challenging.
The majority of subjects with notable responses (tumor reduction and/or >4 months SD) harbored alterations in either or both the PI3K and FA/BRCA gene networks. CCNE gene network alterations (DCR = 67%) partially overlapped with FA/BRCA subjects but was mutually exclusive with PI3K network alterations.
Overall, these data provide promising evidence of SRA737 anti-tumor activity and identify several gene networks associated with potentially enhanced SRA737 sensitivity.
SRA737 Analyst & Investor Event
The company will be hosting an Analyst and Investor Event on Monday, June 3, 2019, to discuss these clinical findings and potential next steps in the development strategy for SRA737+LDG.

Date and Time: June 3, 2019, 6:00 – 7:00 am CT
Location: History event room, Marriot Marquis Hotel, 2121 S Prairie Ave, Chicago, Illinois.

The event will feature presentations by two distinguished oncologists:

Professor Johann de Bono, Regius Professor of Cancer Research, Head of the Division of Clinical Studies and Professor in Experimental Cancer Medicine at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, will discuss the critical role of Chk1 in tumor cell survival during replication stress, as well as describe potential opportunities to combine SRA737 with other therapeutic modalities including PARP inhibitors and immunotherapy agents.
Dr Rebecca Kristeleit, Clinical Senior Lecturer and Honorary Consultant Medical Oncologist at University College London (UCL) Cancer Institute & UCLH Dept. of Oncology, a leading expert in gynecological malignancies, will discuss her clinical experience with SRA737+LDG, and potential development opportunities for this novel combination in the treatment of anogenital cancers.
Event registration and webcast information are available through the Sierra Oncology website at www.sierraoncology.com. An archive of the presentation will be accessible after the event through the Sierra Oncology website.

ASCO 2019 Poster Presentations
Title: A Phase 1/2 First-in-Human Trial of Oral SRA737 (a Chk1 Inhibitor) in Subjects with Advanced Cancer.
Abstract: 3094; Poster #: 86
Poster Session: Developmental Therapeutics and Tumor Biology (Nonimmuno)
Date and Time: Saturday, June 1, 2019, 8:00 – 11:00 am CT
Location: McCormick Place, Event room: Hall A, 2301 S King Dr, Chicago, Illinois

Title: A Phase 1/2 First-in-Human Trial of Oral SRA737 (a Chk1 inhibitor) Given in Combination with Low Dose Gemcitabine in Subjects with Advanced Cancer.
Abstract: 3095; Poster #: 87
Poster Session: Developmental Therapeutics and Tumor Biology (Nonimmuno)
Date and Time: Saturday, June 1, 2019, 8:00 – 11:00 am CT
Location: McCormick Place, Event room: Hall A, 2301 S King Dr, Chicago, Illinois

The posters will be available on June 1, 2019 on the Sierra Oncology website at www.sierraoncology.com

About SRA737 and SRA737+LDG
SRA737 is a potent, highly selective, orally bioavailable small molecule inhibitor of Checkpoint kinase 1 (Chk1), a key regulator of cell cycle progression and the DNA Damage Response (DDR). Tumors with high levels of replication stress become reliant on Chk1 to mitigate the potentially catastrophic consequences of excess genomic instability.

Intrinsic sources of replication stress can include genetic alterations in tumor suppressors, oncogenes or DNA Damage Repair genes. Tumors harboring defects in these gene classes are hypothesized to have higher levels of intrinsic replication stress due to dysregulated cell cycle control, increased proliferation demands and increased genomic instability. SRA737+LDG is a novel drug combination, where non-cytotoxic low dose gemcitabine (LDG) acts as a potent extrinsic inducer of replication stress.

Sierra Oncology retains the global commercialization rights to SRA737.

On June 1, 2019 Replimune Group, Inc. (NASDAQ: REPL), a biotechnology company developing oncolytic immuno-gene therapies derived from its Immulytic platform, reported that the Phase 2 portion of the Company’s Phase 1/2 clinical trial of RP1 alone and in combination with nivolumab anti-PD1 therapy has initiated (Press release, Replimune, JUN 1, 2019, View Source [SID1234536762]). In the Phase 2 portion of the clinical trial, RP1 in combination with nivolumab will be tested in four 30-patient cohorts of patients with melanoma, non-melanoma skin cancers (NMSC), metastatic bladder cancer or microsatellite instability-high (MSI-H) tumors. Enrollment is now open in the melanoma, NMSC and bladder cancer cohorts, and enrollment in the MSI-H cohort will open as soon as a protocol-required MSI-H patient is evaluable from Phase 1. The patients enrolled into the melanoma cohort either will be treatment naïve or have received one prior systemic therapy, and the patients enrolled into the other three cohorts will all be naïve to anti-PD1 therapy.

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

Data relating to the Phase 1 portion of the clinical trial, including biomarker data, is expected to be presented at a medical conference in the fourth quarter of 2019. The Phase 1 portion tested single agent RP1 by direct injection into a single superficial or nodal tumor and by imaging guided injection into a single visceral tumor in patients with advanced heavily pre-treated cancers who failed available therapy to define the recommended Phase 2 dose. Following determination of the recommended Phase 2 dose, an expansion group of advanced cancer patients who failed available therapy then received RP1 at the recommended Phase 2 dose in combination with nivolumab at standard clinical doses.

Poster Presentation at ASCO (Free ASCO Whitepaper)
The Company also announced that a trial in progress (TiP) poster will be presented today at the 2019 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting currently being held in Chicago, IL. The poster describes the design and current status of the Phase 1/2 clinical trial, including the tumor types of the patients enrolled, and will be made available on the Company’s website at the time of presentation.

Details of Replimune’s poster presentation:

Abstract Title: An Open-Label, Multicenter, Phase 1/2 Study of RP1 as a Single Agent and in Combination with PD1 Blockade in Patients with Solid Tumors (Abstract TPS2671)

Session Title: Developmental Immunotherapy and Tumor Immunobiology

Session Date and Time: Saturday June 1st, 8:00am-11:00am CDT

Location: McCormick Place, Exhibit Hall A, Poster Board #301b

About RP1
RP1 is Replimune’s first Immulytic product candidate to enter the clinic and is based on a proprietary new strain of herpes simplex virus engineered to maximize tumor killing potency, the immunogenicity of tumor cell death and the activation of a systemic anti-tumor immune response.

On June 1, 2019 Rakuten Medical, a clinical-stage biotechnology company developing precision-targeted cancer therapies based on its proprietary Photoimmunotherapy (PIT) platform, reported positive data results from its Phase 2a study, evaluating the safety and anti-tumor activity of RM-1929 (an EGFR-targeted antibody conjugate) PIT in patients with locoregional, recurrent head and neck squamous cell carcinoma (rHNSCC) (Press release, Rakuten Aspyrian, JUN 1, 2019, View Source [SID1234536761]). Details of its global Phase 3 study trial design were also presented.

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

The Phase 2a positive data, presented during a poster presentation discussion during the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) annual meeting in Chicago on Saturday, June 1, 2019, showed that treatment with RM-1929 PIT resulted in clinically meaningful activity in 30, heavily pre-treated patients with rHNSCC.

The overall response rate by independent review was 43 percent (95 percent CI 25.5‒62.6), including four (13 percent) complete responses and nine (30 percent) partial responses.
The median, progression-free survival was 5.2 months (95 percent CI 2.1‒5.5), and median overall survival was 9.3 months (95 percent CI 5.2‒16.9).
Treatment with RM-1929 PIT was generally well-tolerated.
Out of the 13 patients (43.3 percent) who experienced a serious adverse event, only three (10 percent) were considered treatment-related.
"Rakuten Medical is committed to addressing the unmet medical needs of patients with cancer, and we are encouraged by the Phase 2a trial data, which demonstrated clinically meaningful anti-tumor activity in patients with late-stage head and neck cancer," said Jeannie Hou, VP of Clinical Development at Rakuten Medical. "We look forward to enrolling patients in our global Phase 3 trial in head and neck cancer."

Phase 3 Trial Overview
Rakuten Medical has initiated its Phase 3, multicenter, randomized, double-arm, open-label trial of ASP-1929 (an EGFR-targeted antibody conjugate; analogous to RM-1929) PIT versus a physician’s choice of standard-of-care for locoregional rHNSCC patients who have failed after at least two lines of therapy, of which at least one line must be systemic, platinum-based chemotherapy for HNSCC.

An overview of the trial background, design and criteria was also presented at ASCO (Free ASCO Whitepaper) during a poster session. The primary endpoints of the study are progression-free survival and overall survival, with the key secondary endpoint being objective response rate. Rakuten Medical expects to enroll approximately 275 patients in the U.S., EU and Asia Pacific.

For more information about the Phase 3 clinical trial (NCT03769506), visit www.clinicaltrials.gov.

About Photoimmunotherapy
Photoimmunotherapy (PIT) is an investigational, anti-cancer treatment platform that is comprised of a drug and device combination that utilizes monoclonal antibodies conjugated to a dye (IRDye 700DX). Transient excitation of IRDye 700Dx with non-thermal red light (690 nm) is believed to result in anti-cancer activity, which is mediated by biophysical processes that may compromise the membrane integrity of cells. The requirement of targeted binding of antibody-IR700 conjugate to a specific antigen on the cell surface and subsequent illumination is believed to result in rapid and selective cell killing and tumor necrosis with minimal effects on surrounding normal tissue. PIT may also lead to the systemic induction of innate and adaptive immunity.