On June 3, 2018 Clovis Oncology, Inc. (NASDAQ:CLVS) and Immunomedics, Inc., (NASDAQ:IMMU) reported their intent to enter into a clinical collaboration to investigate the combination of Clovis’ Rubraca (rucaparib), a poly (ADP ribose) polymerase inhibitor (PARPi), and Immunomedics’ lead antibody-drug conjugate (ADC) product candidate, sacituzumab govitecan, as a treatment of patients with metastatic triple-negative breast cancer (mTNBC) and metastatic urothelial cancer (mUC) (Press release, Clovis Oncology, JUN 3, 2018, View Source [SID1234527115]). The planned phase 1/2 study will include an initial safety cohort followed by expansion cohorts in each of mTNBC and mUC.

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"We look forward to entering this important co-development partnership with Clovis, one of the leading innovative biotech companies, to fully leverage the scientific expertise of both companies and expand the potential for two very active agents," said Usama Malik, Chief Business Officer of Immunomedics. "There is synergy between PARPi and sacituzumab govitecan in preclinical models regardless of BRCA mutation status. This partnership will hopefully provide clinical validation for this exciting concept and bring new treatment options to disease settings with high unmet medical need."

"We are very pleased to partner with Immunomedics and are very enthusiastic about the potential synergy between rucaparib and sacituzumab govitecan," said Patrick J. Mahaffy, President and Chief Executive Officer of Clovis Oncology. "Our plan to initiate new combination studies with Immunomedics further expands our clinical development efforts in both advanced breast and bladder cancers, where there is tremendous need for new treatment options."

In preclinical studies, the combination of sacituzumab govitecan and rucaparib in TNBC cell lines in vitro resulted in synergistic growth inhibition regardless of BRCA1/2 status. In addition, the combination of sacituzumab govitecan and a PARPi also demonstrated significant antitumor effects above that observed with monotherapy in BRCA wild-type and mutant animal models of TNBC.1

"There is an opportunity to develop new treatment options for patients in the mTNBC and mUC space through our planned collaboration with Clovis Oncology, as well as potentially pursuing other indications in the future," stated Dr. Robert Iannone, Head of Research & Development and Chief Medical Officer of Immunomedics. "We are excited by the prospect that our unique ADC in combination with rucaparib could help fill a gap in treatment for cancer patients who have few available options."

Reference

Cardillo TM, Sharkey RM, Rossi DL, et al. Synthetic lethality exploitation by an anti-Trop-2-SN-38 antibody-drug conjugate, IMMU-132, plus PARP inhibitors in BRCA1/2-wild-type triple-negative breast cancer. Clin Cancer Res. 2017 Jul 1;23(13):3405-3415.
About Sacituzumab Govitecan

Sacituzumab govitecan, Immunomedics’ most advanced product candidate, is a novel, first-in-class antibody-drug conjugate (ADC). It is currently under review by the U.S. Food and Drug Administration for accelerated approval as a treatment of patients with triple-negative breast cancer who previously received at least two prior therapies for metastatic disease. If approved, sacituzumab govitecan would be the first and only ADC approved for the treatment of metastatic triple negative breast cancer.

About Rubraca

Rubraca is an oral, small molecule inhibitor of PARP1, PARP2 and PARP3 being developed in multiple tumor types, including ovarian, metastatic castration-resistant prostate, and bladder cancers, as monotherapy, and in combination with other anti-cancer agents. Exploratory studies in other tumor types are also underway. Clovis holds worldwide rights for Rubraca. Rubraca is an unlicensed medical product outside of the U.S. and EU.

Rubraca U.S. FDA Approved Indications and Important Safety Information
Rubraca is indicated as monotherapy for the maintenance treatment of adult patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to platinum-based chemotherapy.

Rubraca is indicated as monotherapy for the treatment of adult patients with deleterious BRCA mutation (germline and/or somatic) associated epithelial ovarian, fallopian tube, or primary peritoneal cancer who have been treated with two or more chemotherapies and selected for therapy based on an FDA-approved companion diagnostic for Rubraca.

Select Important Safety Information
Myelodysplastic Syndrome (MDS)/Acute Myeloid Leukemia (AML) occur uncommonly in patients treated with Rubraca, and are potentially fatal adverse reactions. In approximately 1100 treated patients, MDS/AML occurred in 12 patients (1.1%), including those in long term follow-up. Of these, 5 occurred during treatment or during the 28 day safety follow-up (0.5%). The duration of Rubraca treatment prior to the diagnosis of MDS/AML ranged from 1 month to approximately 28 months. The cases were typical of secondary MDS/cancer therapy-related AML; in all cases, patients had received previous platinum-containing regimens and/or other DNA damaging agents.

Do not start Rubraca until patients have recovered from hematological toxicity caused by previous chemotherapy (≤ Grade 1).

Monitor complete blood counts for cytopenia at baseline and monthly thereafter for clinically significant changes during treatment. For prolonged hematological toxicities (> 4 weeks), interrupt Rubraca or reduce dose (see Dosage and Administration (2.2) in full Prescribing Information) and monitor blood counts weekly until recovery. If the levels have not recovered to Grade 1 or less after 4 weeks or if MDS/AML is suspected, refer the patient to a hematologist for further investigations, including bone marrow analysis and blood sample for cytogenetics. If MDS/AML is confirmed, discontinue Rubraca.

Based on its mechanism of action and findings from animal studies, Rubraca can cause fetal harm when administered to a pregnant woman. Apprise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment and for 6 months following the last dose of Rubraca.

Most common adverse reactions in ARIEL3 (≥ 20%; Grade 1-4) were nausea (76%), fatigue/asthenia (73%), abdominal pain/distention (46%), rash (43%), dysgeusia (40%), anemia (39%), AST/ALT elevation (38%), constipation (37%), vomiting (37%), diarrhea (32%), thrombocytopenia (29%), nasopharyngitis/upper respiratory tract infection (29%), stomatitis (28%), decreased appetite (23%), and neutropenia (20%).

Most common laboratory abnormalities in ARIEL3 (≥ 25%; Grade 1-4) were increase in creatinine (98%), decrease in hemoglobin (88%), increase in cholesterol (84%), increase in alanine aminotransferase (ALT) (73%), increase in aspartate aminotransferase (AST) (61%), decrease in platelets (44%), decrease in leukocytes (44%), decrease in neutrophils (38%), increase in alkaline phosphatase (37%), and decrease in lymphocytes (29%).

Most common adverse reactions in Study 10 and ARIEL2 (≥ 20%; Grade 1-4) were nausea (77%), asthenia/fatigue (77%), vomiting (46%), anemia (44%), constipation (40%), dysgeusia (39%), decreased appetite (39%), diarrhea (34%), abdominal pain (32%), dyspnea (21%), and thrombocytopenia (21%).

Most common laboratory abnormalities in Study 10 and ARIEL2 (≥ 35%; Grade 1-4) were increase in creatinine (92%), increase in alanine aminotransferase (ALT) (74%), increase in aspartate aminotransferase (AST) (73%), decrease in hemoglobin (67%), decrease in lymphocytes (45%), increase in cholesterol (40%), decrease in platelets (39%), and decrease in absolute neutrophil count (35%).

Co-administration of rucaparib can increase the systemic exposure of CYP1A2, CYP3A, CYP2C9, or CYP2C19 substrates, which may increase the risk of toxicities of these drugs. Adjust dosage of CYP1A2, CYP3A, CYP2C9, or CYP2C19 substrates, if clinically indicated. If co-administration with warfarin (a CYP2C9 substrate) cannot be avoided, consider increasing frequency of international normalized ratio (INR) monitoring.

Because of the potential for serious adverse reactions in breast-fed children from Rubraca, advise lactating women not to breastfeed during treatment with Rubraca and for 2 weeks after the last dose.

You may report side effects to the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. You may also report side effects to Clovis Oncology, Inc. at 1-844-258-7662.

Click here for full Prescribing Information and additional Important Safety Information.

On June 3, 2018 Five Prime Therapeutics, Inc. (Nasdaq:FPRX), a clinical-stage biotechnology company focused on discovering and developing innovative immuno-oncology protein therapeutics, reported that a poster titled "FIGHT: A Phase 3 Randomized, Double-Blind, Placebo Controlled Study Evaluating Bemarituzumab (FPA144) and Modified FOLFOX6 (mFOLFOX6) in Patients with Previously Untreated Advanced Gastric and Gastroesophageal Cancer with a Dose Finding Phase 1 Lead-In" was presented today at the 2018 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago (Press release, Five Prime Therapeutics, JUN 3, 2018, View Source [SID1234527078]). The poster (Abstract #TPS4135), is available at View Source

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"Patients with advanced gastric or gastroesophageal junction cancer need new treatment options, particularly those whose tumors overexpress FGFR2b and whose prognosis is especially poor," said Helen Collins, M.D., senior vice president and chief medical officer of Five Prime. "We have seen encouraging monotherapy activity with FPA144 as a late-line treatment for gastric cancer and we believe that combining with chemotherapy in the front-line setting will provide the greatest patient benefit. Our global Phase 1/3 FIGHT trial is studying bemarituzumab in combination with mFOLFOX6 in patients with newly diagnosed gastric and gastroesophageal junction cancer whose tumors overexpress FGFR2b with the goal of providing a new treatment option for patients."

FIGHT Trial

In December 2017, Five Prime initiated the Phase 1 portion (NCT03343301) of the Phase 1/3 FIGHT (FGFR2b Inhibition in Gastric and Gastroesophageal Junction Cancer Treatment) global registrational trial. The Phase 1 safety lead-in portion of the trial is designed to identify a recommended dose of bemarituzumab in combination with the modified FOLFOX6 standard-of-care chemotherapy regimen (mFOLFOX6) to support the initiation of the Phase 3 portion of the trial.

The Phase 3 portion of the FIGHT trial will evaluate bemarituzumab in combination with mFOLFOX6 versus placebo plus mFOLFOX6 in approximately 550 patients with gastric cancer (GC) or gastroesophageal junction (GEJ) cancer whose tumors overexpress FGFR2b. The Phase 3 portion of the trial is expected to begin in the second half of 2018 and will include more than 250 sites in the U.S., Europe and Asia, including China, South Korea and Japan, where the incidence of gastric cancer is high.

The primary endpoint of the FIGHT trial is overall survival (OS) with secondary endpoints of progression-free survival (PFS), objective response rate (ORR), safety and pharmacokinetic (PK) parameters.

Previous Bemarituzumab Trial Results

Data from a Phase 1 clinical trial of single-agent bemarituzumab were presented at the 2017 ASCO (Free ASCO Whitepaper) Annual Meeting. Bemarituzumab demonstrated single-agent activity and an acceptable safety profile in heavily pretreated patients with metastatic gastric cancer whose tumors overexpress FGFR2b.

Efficacy:

In 21 treated patients with late-line GC/GEJ and high FGFR2b overexpression:
ORR was 19.0% with 4 confirmed PRs
Disease control rate was 54.9%
Median duration of response was 15.4 weeks
Overall safety:

Bemarituzumab was well tolerated
There were no dose-limiting toxicities
Maximum tolerated dose was not reached during dose escalation
Unmet Need in GC and GEJ

GC, including GEJ cancer, is the fifth most common cancer worldwide and third leading cause of cancer death. More than 50 percent of GC cases occur in eastern Asia.

Current first-line chemotherapy treatments prolong survival by approximately 6 months compared to best supportive care but median OS remains poor with literature-reported ranges of approximately 10 to 11 months and PFS from 5 to 5.6 months. An unmet medical need exists in the treatment for GC/GEJ since few treatment options following progression are available after first-line chemotherapy.

The presence of FGFR2 amplification or FGFR2b overexpression is associated with a worse prognosis and is present in approximately 10% of patients with GC/GEJ.

FGFs can stimulate transformation and proliferation of tumor cells through signaling mediated by FGF receptors (FGFR 1-4). FGFR2 has 2 splice variants (b and c).

FGFR2b is expressed in tissues of epithelial origin and alterations in FGF/FGFR2 pathway are associated with gastric, breast and other cancers. As a result, targeting this pathway appears to be important in GC/GEJ cancer treatment.

Rationale for Combination with Chemotherapy and Companion Diagnostics

Five Prime made a strategic decision to pursue a front-line bemarituzumab plus chemotherapy combination trial based on preclinical data that showed additive efficacy of bemarituzumab plus chemotherapy. Mutational heterogeneity of GC/GEJ suggests that combining bemarituzumab plus chemotherapy will result in improved activity by acting on non-FGFR2b overexpressing tumor cells and by improving the activity of bemarituzumab in FGFR2b overexpressing tumor cells.

Five Prime is developing companion diagnostics to identify FGFR2b overexpression using an IHC test and FGFR2 gene amplification using ctDNA analysis. Five Prime will use both assays to select patients for the FIGHT trial to identify the estimated 10% of patients with gastric and GEJ tumors that would qualify for the trial.

About Bemarituzumab

Bemarituzumab is a first-in-class, isoform-selective, humanized monoclonal antibody in clinical development as a targeted immunotherapy for tumors that overexpress FGFR2b, a splice variant of a receptor for some members of the fibroblast growth factor (FGF) family. Bemarituzumab has been engineered for enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) to increase direct tumor cell killing by recruiting natural killer (NK) cells. Clinical results to date suggest that the specificity of bemarituzumab avoids the dose-limiting toxicities that have been seen with less selective pan-FGFR tyrosine kinase inhibitors that act on multiple FGFRs, including FGFR2.

Bemarituzumab is being evaluated in the FGF2b Inhibition in Gastric and Gastroesophageal Junction Cancer Treatment (FIGHT) Phase 1/3 clinical trial, a global registrational study in patients with advanced gastric or gastroesophageal junction cancer whose tumors overexpress FGFR2b or have FGFR2 gene amplification. The Phase 3 portion of the trial is expected to begin in the second half of 2018. In December 2017, Five Prime and Zai Lab announced a collaboration for the development and commercialization of bemarituzumab in Greater China. Zai Lab will manage the Phase 3 portion of the FIGHT trial in China.

On June 2, 2018 NantWorks, LLC reported that its affiliate companies, NantHealth, Inc., (NASDAQ: NH), a leading next-generation, evidence-based, personalized healthcare company and NantOmics, LLC, the leader in molecular analysis and a member of the NantWorks ecosystem of companies, will present findings on how targeting immune checkpoints and employing combinations has led to clinical benefit across a variety of tumor types during the tumor biology session at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) 2018 Annual Meeting, an event bringing together 30,000 oncology professionals from June 1-5, 2018 at McCormick Place in Chicago, Illinois (Press release, NantHealth, JUN 2, 2018, View Source;p=RssLanding&cat=news&id=2352872 [SID1234527097]). NantWorks will be exhibiting at booth #7147 during the event.

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"We are excited to share data on how profiling the tumor and associated microenvironment can help tailor rational combinations of immunotherapeutic strategies," said Patrick Soon-Shiong, MD, founder of NantWorks. "This data is an important step in enhancing response rates through individualized immune checkpoints in PD-L1 expression, and we look forward to continued exploration and potential solutions for patients."

Presentation Details

Co-expression patterns of immune checkpoint molecules in relation to PD-L1 expression, Abstract #12113
WHO: NantHealth, LLC and NantOmics, LLC
WHAT: Tumor Biology Session
WHEN: June 4, 1:15-4:45 PM CST
WHERE: Hall A, McCormick Place

Presentation Summary

In order to determine if tailored rational combinations of immunotherapeutic strategies can be achieved by profiling the tumor and associated microenvironment, whole transcriptomic sequencing of 1,880 unselected clinical cases, reflecting 38 distinct histologies, was performed. Cases were categorized as PD-L1-low, PD-L1-normal and PD-L1-high by cutoffs defined in TCGA expression profiles. The results found that high and low PD-L1 expression in the tumor and adjacent microenvironment are associated with variations in key checkpoint molecules. The results also found that low expression of PD-L1 may be an ideal setting for use of IDO- or TIM3-directed therapies.

On June 2, 2018 NantWorks, LLC reported that its affiliate companies, NantHealth, Inc., (NASDAQ: NH), a leading next-generation, evidence-based, personalized healthcare company and NantOmics, LLC, the leader in molecular analysis and a member of the NantWorks ecosystem of companies, the leader in molecular diagnostics and a member of the NantWorks ecosystem of families, reported that it will present data on three-fold overestimation of tumor mutation burden (TMB) using a 248 gene list as a panel to impute TMB during the tumor biology session at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) 2018 Annual Meeting, an event bringing together 30,000 oncology professionals from June 1-5, 2018 at McCormick Place in Chicago, Illinois. NantWorks will be exhibiting at booth #7147 during the event.

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The data presented here have significant implications on the use of immunotherapies such as Keytruda and Opdivo given previous data touting the effectiveness of these drugs in patients whose tumors bear high TMB. The NantWorks companies’ data presented here caution against overestimation of TMB and thus immunotherapy overuse when extrapolating TMB from smaller panel tests (<500 genes) versus simply identifying all actual mutations by surveying the entire genome. Further, whether performing analysis on the entire genome or in a panel test, clinical validity for the use of immunotherapies is made appreciably more precise by confirming the expression of identified mutations. The patient’s immune system recognizes and targets non-self proteins, not DNA, thus underscoring the need to append the mutated genomic data with expression data. Maximal accuracy as established in this presentation by the use of tumor-normal DNA interpretation of TMB from surveying all genes and further amplified by derivation of expressed TMB is what is required for future immunotherapies such as neoepitope vaccines.

"We’re excited to share our data from our retrospective analysis, which may impact ICT prescription and expectation of clinical benefit," said Patrick Soon-Shiong, MD, founder of NantWorks. "Our analysis builds on our breadth of actionable insight and molecularly driven support for cancer patients and their providers, and we look forward to continuing to build upon our diagnostic capabilities."

Presentation Details

Three-fold overestimation of tumor mutation burden using 248 gene panel versus whole exome, Abstract, #12117
WHO: NantHealth, LLC and NantOmics, LLC
WHAT: Tumor Biology Session
WHEN: June 4, 1:15-4:45 PM CST
WHERE: Hall A, McCormick Place

Presentation Summary

This study analyzed if actual TMB (aTMB), consisting of mutations across the exome, and expressed TMB (eTMB), consisting of expressed genes, would differ substantially from iTMB. Retrospective analysis of a database from a commercial DNA tumor:normal and RNAseq platform was carried out. 890 clinical samples were analyzed, composing of both primary and metastatic disease by whole genome sequencing (WGS) or WES and RNA sequencing (RNA-Seq), and compared true tumor mutational burden to a predicted tumor mutational burden from a list of 248 genes thought to drive cancer. The study showed an estimated tumor mutational burden based only on the list of 248 genes had an average of 15.79 mutations per megabase whereas WGS/WES derived TMB had an average of 5.09 mutations per megabase of coding DNA. As a result, the study indicates that a roughly 3-fold over-estimate of TMB was observed, which may impact ICT prescription and expectation of clinical benefit.

On June 2, 2018 Celldex Therapeutics, Inc. (NASDAQ:CLDX) today presented two programs at the 2018 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago (Press release, Celldex Therapeutics, JUN 2, 2018, View Source [SID1234527065]). Data from the Phase 1/2 study of Celldex’s varlilumab, a CD27 targeting investigational immune-activating antibody, and Bristol-Myers Squibb’s Opdivo (nivolumab), an anti-PD1 immunotherapy, for patients with ovarian cancer and colorectal cancer, were presented in an oral session by Rachel E. Sanborn, M.D., Co-director of the Providence Thoracic Oncology Program and Phase 1 Clinical Trials Program, at the Earle A. Chiles Research Institute, Providence Cancer Institute, in Portland, Ore. In addition, an overview of the Phase 2 study of the anti-ErbB3 antibody CDX-3379 in combination with Erbitux in advanced head and neck squamous cell cancer was presented in a "clinical trials in progress" poster session.

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"The data presented today continue to support that varlilumab holds considerable potential as an immune activator," said Dr. Sanborn. "This was particularly noteworthy in ovarian cancer where the combination with the anti-PD1 monoclonal antibody, Opdivo, turned "immune-cold" tumors "hot," which in turn correlated with improved clinical outcomes, including improved response rate and progression-free survival in these patients."

"Moving forward, we believe more work needs to be done to identify synergistic combinations and patient populations that have the best chance of responding to varlilumab treatment," said Tibor Keler, Ph.D., Executive Vice President and Chief Scientific Officer of Celldex Therapeutics. "We are continuing to explore these opportunities through inclusion in our ongoing Phase 1 study of CDX-1140, our CD40 agonist antibody, and several investigator-initiated studies."

"We also continue to enroll patients into our ongoing Phase 2 study of CDX-3379 in combination with Erbitux in patients with HPV negative, Erbitux-resistant, advanced head and neck squamous cell carcinoma. We look forward to completing enrollment to the first stage of this study in the third quarter of 2018 and are exploring other potential opportunities in indications where ErbB3 is believed to play a role," concluded Dr. Keler.

ASCO Highlights

Varlilumab

Varlilumab was featured in an oral presentation that highlighted the ongoing Phase 2 study of varlilumab in combination with Opdivo. The Phase 1/2 study includes cohorts in ovarian cancer, colorectal cancer, head and neck squamous cell carcinoma, renal cell carcinoma and glioblastoma, with data from ovarian cancer (n=66) and colorectal cancer (n=42) patients included in the presentation today. The majority of patients enrolled in the study had baseline tumors that were mostly "cold" (PD-L1 negative or low, and low tumor-infiltrating lymphocyte [TIL] levels) with low expectation of responding to checkpoint inhibition therapy. The combination was well tolerated at all varlilumab dose levels tested.

Results in Ovarian Cancer Experience: n=66, 8 patients in Phase 1; 58 patients in Phase 2; median of three prior lines of therapy; 91% had Stage IV disease; 66% with PD-L1 negative tumors; multiple varlilumab dosing regimens evaluated. Detailed information by dosing cohort is included in the presentation and is available on the Celldex website.

Overall response rate: 14% (n=9) across 64 response-evaluable patients (7 confirmed, 2 unconfirmed)
Response rate by PD-L1 status:
PD-L1 positive: 20% (n=4 of 20; 3 confirmed, 1 unconfirmed)
PD-L1 negative: 14% (n=5 of 37; 4 confirmed, 1 unconfirmed)
Disease control rate (DCR), defined as best response of stable disease or better for greater than or equal to three months, was 38% (n=24 of 64). As of the cut-off for analysis, five patients continued on treatment.
For patients with tumor samples available, most patients experienced increases in tumor expression of PD-L1 (n=14 of 23; 61%) and CD8+ TIL levels (n=14 of 24; 58%). These increases were associated with improved clinical outcome, including improved progression-free survival (PFS) and response rate.

Results in Colorectal Cancer Experience: n=42; 21 patients in Phase 1; 21 patients in Phase 2; median of four prior lines of therapy; 100% had Stage IV disease; 87% had PD-L1 negative tumors; one patient was MSI-high and 21 patients were MSI-low/mismatch repair (MMR) proficient; MSI status for the remaining 20 patients was unknown.

One patient with PD-L1 negative, MSI-high disease experienced a confirmed partial response in the Phase 2 study portion and continues on treatment. Of note, a patient with PD-L1 negative disease, initially considered MMR proficient as determined by standard screening laboratory analysis, achieved a near complete response in the Phase 1 portion of the study, which now continues at 35 months. As part of this study, an additional molecular analysis was conducted on this patient’s tumor. The tumor had a high mutational burden and mutations in genes regulating DNA repair, which together likely contributed to the response. DCR was 20% (8/41).
CDX-3379

CDX-3379 was featured in a "clinical trials in progress" poster presentation, available on the Celldex website, that highlighted the ongoing Phase 2 study of CDX-3379, a human monoclonal antibody designed to block the activity of ErbB3 (HER3), in combination with Erbitux in patients with human papillomavirus (HPV) negative, Erbitux-resistant, advanced head and neck squamous cell carcinoma. The proposed mechanism of action for CDX-3379 sets it apart from other drugs in development in this class due to its ability to block both ligand-independent and ligand-dependent ErbB3 signaling by binding to a unique epitope. It has a favorable pharmacologic profile, including a longer half-life and slower clearance relative to other drug candidates in this class. The multicenter, open-label, Simon two-stage design study is expected to enroll approximately 27 patients (Stage 1=13; Stage 2=14). The primary objective of the study is objective response rate. Secondary objectives include assessments of clinical benefit response, duration of response, progression-free survival and overall survival, and safety and pharmacokinetics associated with the combination. Four clinical trial sites are currently open to enrollment, and Celldex is targeting to complete enrollment to the first stage of the study by the end of the third quarter of 2018. The Company continues to explore potential other opportunities in additional indications where ErbB3 is believed to play a role.