On December 2, 2018 Unum Therapeutics Inc. (NASDAQ: UMRX), reported preliminary results from the ongoing, multicenter Phase 1 ATTCK-20-03 study of ACTR707 in combination with rituximab in patients with relapsed/refractory CD20+ B cell non-Hodgkin lymphoma (r/r NHL) at the American Society of Hematology (ASH) (Free ASH Whitepaper) meeting in San Diego, CA (Press release, Unum Therapeutics, DEC 2, 2018, View Source [SID1234531811]).

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Unum presented updated data from all patients in the first two dose levels of ACTR707 in combination with rituximab. First-in-human dosing was well tolerated, with no dose-limiting toxicities observed and no serious or severe adverse events of cytokine release syndrome (CRS) or neurological events observed in any patients. Three of the six patients treated at dose level 1 achieved a complete response, two of which were ongoing with greater than 6 months follow up, as of the November 1, 2018 cutoff. One of the three patients in dose level 2 also achieved a complete response, which remained ongoing as of the November 1 cutoff. Based on these data, enrollment in dose level 3 is progressing as planned.

"These preliminary results demonstrate ACTR T cell activity with complete responses at both dose levels, dose-dependent ACTR707 expansion, and a well-tolerated safety profile, supporting further dose escalation," said Michael Vasconcelles, Chief Medical Officer of Unum. "We are encouraged by these data and the potential of ACTR707 plus rituximab to have a best-in-class profile relative to CD19-directed CAR-T therapies in this heavily pretreated patient population with aggressive non-Hodgkin lymphoma."

Pharmacodynamic evidence of activity of ACTR707 in combination with rituximab supporting the proof of mechanism includes dose-dependent peak ACTR707 expansion and ACTR707 persistence, detectable > 200 days in the peripheral blood post ACTR707 infusion. Additionally, no impact of ACTR707 on the pharmacokinetics of rituximab has been observed. ACTR707-related serious adverse events were febrile neutropenia in 2 patients and 1 case of pancytopenia.

About the ATTCK-20-03 Trial

ATTCK-20-03 is a Phase I, multi-center, open label, single arm clinical trial evaluating ACTR707 in combination with rituximab in patients with r/r NHL. Eligible patients for enrollment must have, among other criteria, received adequate prior anti-lymphoma therapy, including anti-CD20 monoclonal antibody and chemotherapy, for their CD20+ r/r NHL. Key eligibility criteria include: pre-specified eligible NHL subtypes, including DLBCL, disease progression following immediate prior therapy, adequate organ function and performance status, and measurable disease. The trial design includes a dose escalation phase using an adaptive design, followed by a cohort expansion phase. Primary study objectives are to characterize the safety of ACTR707 in combination with rituximab and to determine the maximum tolerated dose and proposed recommended Phase 2 dose. Secondary study objectives include: assessment of the anti-lymphoma activity of the combination, ACTR707 persistence, rituximab pharmacokinetics, and inflammatory markers and cytokine levels. Following leukapheresis, each patient receives lymphodepletion followed by the first infusion of rituximab and then a single infusion of ACTR707. Rituximab infusions continue on a regular, pre-specified schedule.

About ACTR707
ACTR707 is an investigational drug that is being evaluated in adult patients with CD20+ r/r NHL in combination with rituximab as well as in adult patients with other cancer types in combination with other antibodies. ACTR707 was identified through a comprehensive high-throughput screening effort aimed at identifying receptors with improved functional characteristics across several dimensions. In preclinical testing, ACTR707 demonstrated potent activity against a wide range of hematologic and solid tumor cancers. Given the challenges of the immunosuppressive solid tumor microenvironment, Unum believes that ACTR707’s increased activity may be particularly important in addressing solid tumor cancers. ACTR707 is currently being tested in combination with rituximab in patients with r/r NHL in a Phase I multi-center open label clinical trial, ATTCK-20-03. Testing is expected to be initiated later in 2018 in ATTCK-34-01, a Phase I multi-center open label clinical trial exploring the combination of ACTR707 with trastuzumab in patients with HER2+ advanced cancers.

On December 2, 2018 MEI Pharma, Inc. (NASDAQ: MEIP), a late-stage pharmaceutical company focused on advancing new therapies for cancer, reported that results from an ongoing Phase 1b study support the complementary potential of intermittent and continuous dosing schedules of ME-401, a selective phosphatidylinositol 3-kinase ("PI3K") delta inhibitor, to optimize the clinical risk-benefit ratio in patients with relapsed/refractory follicular lymphoma (Press release, MEI Pharma, DEC 2, 2018, View Source [SID1234531809]). The data demonstrate that ME-401, as both a single agent and in combination with rituximab, continues to be associated with overall high objective response rates. In addition, low rates of Grade 3 immune-related adverse events (irAEs) were observed in patients on the intermittent dosing schedule while maintaining a high level of clinical response. These data are being presented today at the 2018 American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting.

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The data announced today continue to support the rationale for MEI’s planned Phase 2 study that evaluates both a continuous (CS) and intermittent (IS) dosing schedule of ME-401 as a means to enhance the drug candidate’s clinical profile and thus potentially deliver improved benefits to patients. The Phase 2 study is expected to start around year-end and is intended to support MEI’s accelerated approval registration strategy if successful.

Patients in the Phase 1b study received ME-401 as a single agent (dosed on the CS or IS) and in combination with rituximab (dosed on the IS only) to explore treatment options for patients with B-cell malignancies. The IS dosing regimen consists of 60 mg given continuously, once-daily, for the first 2 cycles followed by 60 mg given on days 1-7 of a 28-day cycle and results showed:

As a single agent, 76% objective response rate in patients with relapsed or refractory follicular lymphoma (FL), and 100% in all patients with chronic lymphocytic lymphoma (CLL) and small lymphocytic lymphoma (SLL).
In combination with rituximab, 78% objective response rate in patients with FL.
Median duration of response has not been reached. The lead patient has a duration of response of approximately 20 months and the median follow-up is 9.3 months.
Low rate of irAEs; 4 irAEs were reported in 36 patients administered the IS, with all cases occurring in the first 2 cycles following the switch to IS.
89% of patients switched to IS remain on therapy.
Disease control was maintained in 72% of these patients.
70% of patients who resumed on the continuous daily dosing schedule (CS) recaptured a response after progressing on IS.
The ME-401 ASH (Free ASH Whitepaper) 2018 poster can be accessed on the MEI Pharma website.

"The data presented today are very supportive of our rationale to investigate both a continuous and intermittent dosing regimen as part of our Phase 2 study evaluating ME-401 in follicular lymphoma and may also help advance its complementary potential to deliver improved benefits to patients in combination with other modalities," said Daniel P. Gold, Ph.D., president and chief executive officer of MEI Pharma. "While advances have been made in the treatment of B-cell malignancies, there remains a significant need for innovative therapies across a range of indications and patient populations not addressed by current therapeutic options; we believe the emerging clinical profile of ME-401, as both a single agent or in combination, holds the potential to deliver improved clinical benefit to patients with B-cell diseases."

ME-401 Phase 1b ASH (Free ASH Whitepaper) 2018 Data
ME-401 is being evaluated in an ongoing Phase 1b dose escalation study in patients with relapsed or refractory B-cell malignancies. Through October 2018, 60 patients were enrolled across three groups:

Group 1 included 31 patients with relapsed FL (n = 22) or CLL/SLL (n = 9) who received ME-401 CS at doses ≥60 mg per day in the dose escalation phase of the study. Beginning in December 2017 a total of 17 patients from Group 1 (FL=9, CLL/SLL=8) advanced to the IS after in cycle 4 or later cycles.
Group 2 included 16 patients with relapsed FL (n = 9), diffuse large B-cell lymphoma (n = 5), marginal zone lymphoma (MZL, n = 1), and CLL (n = 1) who received rituximab 375 mg/m2 x 8 doses over 6 months and ME-401 dosed under the IS regimen after receiving ME-401 60 mg daily for the first two cycles.
Group 3 may enroll up to 30 patients with relapsed FL/CLL/SLL in an expansion cohort of ME-401 using the IS regimen after receiving ME-401 60 mg daily for the first two cycles. In this group, 13 patients were enrolled to date with one FL patient reaching the Cycle 6 disease assessment as data cut off.
The median number of prior therapies of patients in the study is two and 50% of patients enrolled were ≥ 3rd line of therapy. Responses are assessed after 2 cycles (58 days) and 6 cycles, and then every 6 cycles. Ninety-two percent of all patients were previously treated with an anti-CD20 antibody.

Objective Response Rates

The objective response rate of patients across all groups with FL is 76% (29/38) and for CLL/SLL is 100% (11/11).
As a single agent, 76% (22/29) objective response rate in patients with FL and 100% (10/10) in patients with CLL and SLL.
In combination with rituximab, 78% (7/9) objective response rate in patients with FL.
Duration of Response

In FL and CLL/SLL patients, the median follow-up is 9.3 months (range, approximately 2.1 to 19.5 months) with no median yet reached.
Across all groups, failure-free survival (i.e. no disease progression on the continuous dosing schedule) in FL and CLL/SLL has not reached a median yet; median follow-up is 6.9 months (range 0.4 to 21.1 months).
72% of patients across all groups on the IS regimen have not experienced disease progression with a median follow-up of 7.9 months (range, 0.8 to 10.5 months).
Of the 10 patients that progressed on the IS regimen, 70% of patients retreated with daily dosing recaptured disease response.
Rates of irAEs

Of the 36 patients who switched to IS, only 11% (4/36) experienced an irAE after the switch. All 4 reported cases of irAEs occurred in the first 2 cycles after the switch to the IS regimen.
About ME-401
ME-401 is an investigational oral phosphatidylinositol 3-kinase ("PI3K") delta inhibitor; PI3K delta is often overexpressed in cancer cells and plays a key role in the proliferation and survival of hematologic cancer cells. ME-401 displays high selectivity for the PI3K delta isoform and has distinct pharmaceutical properties from other PI3K delta inhibitors. It is being clinically evaluated in patients with various B-cell malignancies. MEI is initiating a Phase 2 study to evaluate the efficacy, safety, and tolerability of ME-401 as a single agent in patients with follicular lymphoma after failure of at least two prior systemic therapies including chemotherapy and an anti-CD20 antibody. The Phase 2 study is intended to support an accelerated approval marketing application with the U.S. Food and Drug Administration.

On December 2, 2018 Aprea Therapeutics reported results at the 2018 ASH (Free ASH Whitepaper) Annual Meeting from its Phase Ib/II clinical study in MDS (Press release, Aprea, DEC 2, 2018, View Source [SID1234531805]). The ongoing study is evaluating the safety and efficacy of APR-246 in combination with azacitidine for the treatment of TP53 mutated MDS. The study is sponsored by the Moffitt Cancer Center with financial support from the MDS Foundation and the Aplastic Anemia and MDS International Foundation as administrator for the Evans MDS Clinical Research Consortium.

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The overall response rate in 20 evaluable patients was 95%, with 14 (70%) patients achieving a complete remission (CR) at data cutoff. Relative to baseline, p53 immunohistochemistry positivity, mutant TP53 variant allele frequency (VAF) and TP53 minimal residual disease (MRD) were significantly decreased at time of disease assessment. No dose-limiting toxicities have been experienced to date and no exacerbation of the expected AZA-related safety profile has been observed.

"The expanding data set from this study is very encouraging," said David Sallman, M.D., lead principal investigator of the clinical study from the Moffitt Cancer Center. "As of this latest data cutoff, responses have been achieved in nearly all patients, including a 70% complete remission rate, and accompanied by deep molecular remission in the majority of patients as assessed by serial TP53 analysis. In addition, the overall safety experience indicates that the combination regimen of APR-246 and azacitidine is both safe and well-tolerated. Comparison of the current data set to historical AZA clinical experience suggests that combination of APR-246 with AZA may offer these patients a better potential treatment option than AZA alone."

"The continued positive data from this clinical study has created the potential for a new treatment paradigm for patients with few therapeutic options," said Christian S. Schade, President and Chief Executive Officer of Aprea. "As a result of this exciting progress, Aprea expects to soon begin enrolling a randomized, controlled Phase III clinical study of APR-246 in combination with AZA for the treatment of TP53 mutated MDS."

About the Clinical Study

Eligible patients in the Phase Ib/II clinical study include HMA naïve, TP53 mutated MDS and oligoblastic acute myeloid leukemia (AML, ≤ 30% blasts). In the Phase Ib part of the clincal study, patients received APR-246 in a 3+3 dose escalation design (50, 75, 100 mg/kg lean body weight) IV daily over 4 days in a lead-in phase (days -14 to -10), followed by the same dose of APR-246 (days 1-4) and AZA 75 mg/m2 SC/IV over 7 days (days 4-10 or 4-5 and 8-12) in 28-day cycles. In the Phase II part of the clinical study, patients receive APR-246 as a 4,500 mg fixed dose IV daily (days 1-4) and AZA over 7 days (days 4-10 or 4-5 and 8-12) in 28-day cycles. Primary objective in Phase Ib part of the clinical study was safety, with AEs graded by CTCAE v4.03 and DLT assessment over 6 weeks. Secondary endpoints included response rate by IWG 2006 criteria, PFS, OS, as well as serial next generation sequencing and p53 immunohistochemistry for evaluation of clonal suppression and depth of remission. In the Phase II part of the clinical study the primary endpoint is response rate.

About Myelodysplastic Syndrome

Myelodysplastic syndromes (MDS) represents a spectrum of hematopoietic stem cell malignancies in which bone marrow fails to produce sufficient numbers of healthy blood cells. Approximately 30-40% of MDS patients progress to acute myeloid leukemia (AML) and mutation of the p53 tumor suppressor protein is thought to contribute to disease progression. Mutations in p53 are found in up to 20% of MDS and AML patients and are associated with poor overall prognosis.

About p53 and APR-246

The p53 tumor suppressor gene is the most frequently mutated gene in human cancer, occurring in approximately 50% of all human tumors. These mutations are often associated with resistance to anti-cancer drugs and poor overall survival, representing a major unmet medical need in the treatment of cancer.

APR-246 has been shown to reactivate mutant and inactivated p53 protein – by restoring wild-type p53 conformation and function – and thereby induce programmed cell death in human cancer cells. APR-246 has demonstrated pre-clinical anti-tumor activity in a wide variety of solid and hematological (blood) tumors, including MDS, AML, and ovarian cancer, among others. Additionally, strong synergy has been seen with both traditional anti-cancer agents, such as chemotherapy, as well as newer mechanism-based anti-cancer drugs and immuno-oncology checkpoint inhibitors. In addition to pre-clinical testing, a Phase I/II clinical program with APR-246 has been completed, demonstrating a favorable safety profile and both biological and confirmed clinical responses in hematological malignancies and solid tumors with mutations in the TP53 gene.

On December 2, 2018 Celgene Corporation (NASDAQ: CELG) and Acceleron Pharma Inc. (NASDAQ: XLRN) reported results from the pivotal, phase 3 MEDALIST trial evaluating the efficacy and safety of investigational luspatercept to treat patients with ring sideroblast (RS+) myelodysplastic syndromes (MDS)-associated anemia who require red blood cell transfusions and who had failed, were intolerant to, or ineligible for erythropoietin therapy (Press release, Celgene, DEC 2, 2018, View Source [SID1234531801]). Results were presented by Alan F. List, M.D. during the Plenary Scientific Session at the 60th American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting and Exposition in San Diego, C.A. (Abstract #1).

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"Severe anemia resulting in red blood cell transfusion dependence is a significant challenge for patients with low- and intermediate-risk MDS. Those who become resistant or refractory to currently available treatments have limited alternatives," said Dr. List, President and CEO of Moffitt Cancer Center. "The findings from MEDALIST are very exciting as they support the hypothesis that targeting red blood cell precursor maturation could help to address patients’ anemia and allow them to achieve transfusion independence."

MEDALIST met the primary endpoint of red blood cell transfusion independence (RBC-TI) for 8 or more weeks during the first 24 weeks of the study. Treatment with luspatercept resulted in a statistically significantly greater proportion of patients achieving RBC-TI ≥ 8 weeks compared to placebo. The study also found in secondary endpoints that treatment with luspatercept resulted in a statistically significant higher percentage of patients achieving RBC-TI of 12 or more weeks in the first 24 or 48 weeks of the study, as well as hematologic improvement-erythroid (HI-E) of 8 or more weeks.

Endpoints Luspatercept Placebo P-Value
RBC-TI ≥8 weeks (weeks 1-24) 37.9 % (58/153) 13.2 % (10/76) < 0.0001
RBC-TI ≥12 weeks (weeks 1-24) 28.1 % (43/153) 7.9 % (6/76) 0.0002
RBC-TI ≥12 weeks (weeks 1-48) 33.3 % (51/153) 11.8 % (9/76) 0.0003
HI-E ≥ 8 weeks (IWG 2006, weeks 1-24) 52.9 % (81/153) 11.8 % (9/76) < 0.0001

MEDALIST Safety Summary

Treatment-emergent adverse events (TEAEs) of Grade 3 or 4 were reported in 42.5% (65/153) of patients receiving luspatercept and 44.7% (34/76) of patients receiving placebo. Progression to acute myeloid leukemia (AML) occurred in four patients, three patients (2.0%) receiving luspatercept and one patient (1.3%) receiving placebo. Five patients receiving luspatercept (3.3%) and four patients receiving placebo (5.3%) experienced one or more TEAE that resulted in death.

Most common TEAEs of any Grade in Greater than 10% of Patients in Either Arm

Luspatercept
N=153

Placebo
N=76

Fatigue 26.8 % 13.2 %
Diarrhea 22.2 % 9.2 %
Asthenia 20.3 % 11.8 %
Nausea 20.3 % 7.9 %
Dizziness 19.6 % 5.3 %
Back pain 19.0 % 6.6 %

"The MEDALIST results demonstrate the potential clinical benefit of luspatercept in achieving red blood cell transfusion independence in patients with low-to-intermediate risk RS+ MDS, an area in need of new treatments," said Alise Reicin, MD, President, Global Clinical Development for Celgene. "Based on these results, we are encouraged that this first-in-class erythroid maturation agent may help these patients address the underlying cause of their disease-related chronic anemia."

"It’s truly an honor to showcase the results from the MEDALIST trial as the first presentation of the ASH (Free ASH Whitepaper) Plenary Session," said Habib Dable, President and Chief Executive Officer of Acceleron. "The results from the MEDALIST trial increase our confidence in the potential of luspatercept to provide a meaningful treatment option for patients suffering from lower-risk RS+ MDS worldwide. We’re excited to continue our clinical development program in MDS, beta-thalassemia, and myelofibrosis, while also exploring additional applications for luspatercept in a range of diseases associated with anemia."

Luspatercept is not approved in any region for any indication. The companies are planning regulatory application submissions of luspatercept in the United States and Europe in the first half of 2019.

About MEDALIST

MEDALIST is a phase 3, randomized, double blind, placebo-controlled, multi-center study evaluating the safety and efficacy of luspatercept in patients with very low-, low-, or intermediate-risk non-del(5q) myelodysplastic syndromes (MDS). All patients were RBC transfusion dependent and were either refractory or intolerant to prior erythropoiesis-stimulating agent (ESA) therapy, or were ESA naïve with endogenous serum erythropoietin ≥ 200 U/L, and had no prior treatment with disease modifying agents. The median age of the patients enrolled in the trial was 71 years in the luspatercept treatment group and 72 years in the placebo group. Median transfusion burden in both treatment arms was 5 RBC units/8 weeks. 229 patients were randomized to receive either luspatercept 1.0 mg/kg (153 patients) or placebo (76 patients) via subcutaneous injection once every 21 days. The study was conducted at 65 sites in 11 countries.

About Luspatercept

Luspatercept is a first-in-class erythroid maturation agent (EMA) that is believed to regulate late-stage red blood cell maturation. Acceleron and Celgene are jointly developing luspatercept as part of a global collaboration. Phase 3 clinical trials continue to evaluate the safety and efficacy of luspatercept in patients with MDS (the MEDALIST trial) and in patients with beta-thalassemia (the BELIEVE trial). The COMMANDS phase 3 trial in first-line, lower-risk, MDS patients, the BEYOND phase 2 trial in non-transfusion-dependent beta-thalassemia, and a phase 2 trial in myelofibrosis are ongoing. For more information, please visit www.clinicaltrials.gov.

On December 2, 2018 Kura Oncology, Inc. (Nasdaq: KURA), a clinical-stage biopharmaceutical company focused on the development of precision medicines for oncology, reported preliminary data in angioimmunoblastic T-cell lymphoma (AITL) and CXCL12+ peripheral T-cell lymphoma (PTCL), the two expansion cohorts in its Phase 2 clinical trial of its lead drug candidate tipifarnib in patients with relapsed or refractory PTCL (Press release, Kura Oncology, DEC 2, 2018, View Source [SID1234531800]).

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The data, presented today at the American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting in San Diego, showed encouraging activity with tipifarnib in late-stage PTCL patients, including a significant association between CXCL12 expression and clinical benefit, and proof of concept in AITL, an aggressive form of T-cell lymphoma often characterized by high levels of CXCL12 expression. A copy of the poster is available on the Company’s website at www.kuraoncology.com.

"The mechanism of action of farnesyl transferase inhibitors has remained elusive for several decades," said Antonio Gualberto, M.D., Ph.D., Head of Development and Chief Medical Officer of Kura Oncology. "Our initial data in HRAS mutant head and neck cancer provided strong evidence of activity in tumors driven by this oncogene. However, many other tumors such as T- and B-cell lymphomas, myeloid leukemias, pancreatic or breast cancers, in which anecdotal evidence of tipifarnib activity has been reported, do not usually carry HRAS mutations. We believe the preliminary results reported at ASH (Free ASH Whitepaper) validate our observation that the CXCL12 pathway is a therapeutic target of tipifarnib and provide a potential path to expand the development of tipifarnib well beyond HRAS mutant solid tumors by using CXCL12-related biomarkers to enrich for patients most likely to benefit from treatment. We will continue our efforts to identify these patient subsets and to bring this important drug candidate to patients in need."

As of November 21, 2018, a total of 39 patients were enrolled in the ongoing Phase 2 trial, including 19 patients with AITL (16 patients in the AITL extension cohort and 3 patients in the previous portion of the study). Six of the 16 AITL patients were not evaluable as of the data cutoff date, including two who were pending initial efficacy assessments. Of the 13 evaluable AITL patients, two achieved a complete response (CR) and four achieved a partial response (PR), for an objective response rate (ORR) of 46% (six of 13). According to the study protocol, the AITL cohort is considered positive when four or more responses are observed.

The study also identified a particularly responsive subset within AITL and non-AITL patients. Specifically, patients with a high ratio of expression of CXCL12 to its receptor CXCR4 experienced a 50% ORR (five of 10) and a 90% clinical benefit rate (nine of 10 with either complete response, partial response or stable disease) with tipifarnib. Patients in this Phase 2 trial had a median of three prior lines of therapy (range 1-7). The high CXCL12/CXCR4 expression ratio had 90% sensitivity and 93% specificity to identify PTCL patients likely to benefit from tipifarnib.

In addition to the Phase 2 clinical data, the results from two ancillary, non-clinical studies were also reported at ASH (Free ASH Whitepaper). In the first, the expression of CXCL12 and CXCR4 was investigated using tumor bank samples of PTCL patients treated with standard-of-care agents. Worse prognosis was observed in PTCL patients with high CXCL12/CXCR4 expression ratio, indicating that CXCL12 is a negative prognostic factor for standard PTCL therapy. In the second study, the effect of the incubation of stroma cells with tipifarnib on CXCL12 secretion was investigated in a mouse model of bone marrow culture. Tipifarnib reduced secretion of the CXCL12 chemokine from the stromal cells, providing a potential mechanism of action for the observed clinical activity.

"To our knowledge, these results position tipifarnib as the first CXCL12 inhibitor with reported proof-of-concept data, marking a significant advancement in our development strategy," said Troy Wilson, Ph.D., President and CEO of Kura Oncology. "Our data suggest that as many as 40% of PTCL patients express high CXCL12. In addition, the discovery of CXCL12-related biomarkers offers the potential to increase the opportunity for tipifarnib into other hematological and solid tumor indications. We intend to explore those indications while continuing to gather additional data from our ongoing Phase 2 study and expect to provide an update at a medical meeting next year."

The Phase 2 study was designed to investigate the anti-tumor activity of tipifarnib in patients with relapsed or refractory PTCL. After preliminary data suggested that CXCL12 expression was associated with tipifarnib’s clinical activity, two expansion cohorts were added to enroll patients with tumors expected to overexpress CXCL12: AITL tumors, and those non-AITL tumors that lack a single nucleotide variation in the 3’-untranslated region (3′-UTR) of the CXCL12 gene (CXCL12+ PTCL). CXCL12 is a stroma-derived chemokine that promotes the progression of lymphoma and other hematological and solid tumors carrying the CXCR4 receptor, and our previous results had suggested an association between CXCL12 expression and the most common form of the 3’-UTR CXCL12 variant. In the expansion cohorts, both the presence or absence of this variant and the expression levels of CXCL12 and CXCR4 were assessed.

In the expansion cohorts in the Phase 2 trial tipifarnib was dosed at 300 mg twice daily on days 1-21 of a 28-day cycle. The reported data indicated that tipifarnib was generally well-tolerated, with adverse events consistent with its known safety profile. The most common treatment-related adverse events (grade ≥ 3) were hematology-related, including neutropenia, thrombocytopenia, leukopenia, febrile neutropenia and anemia.

Last week, the U.S. Patent and Trademark Office (USPTO) issued a new patent for tipifarnib as a method of treating patients with AITL. In May 2018, the USPTO issued a patent for tipifarnib as a method of treating patients with certain CXCL12-expressing cancers, including PTCL. Both patents expand protection for tipifarnib, providing exclusivity in the U.S. to 2037.

Webcast Information

Kura’s management will host a webcast at 11:30 p.m. ET / 8:30 p.m. PT today, December 2, 2018, following the conclusion of the poster presentation at the ASH (Free ASH Whitepaper) 2018 Annual Meeting. The live audio webcast and slides of the presentation will be available from the Investors and Media section of the company website at www.kuraoncology.com, and will be archived there for 30 days.

About Tipifarnib

Kura Oncology’s lead drug candidate, tipifarnib, is a potent and highly selective inhibitor of farnesylation, a key cell signaling process implicated in cancer initiation and development. Tipifarnib was previously studied in more than 5,000 cancer patients and showed compelling and durable anti-cancer activity in certain patient subsets, however no molecular mechanism of action had previously been determined that could explain its activity across a range of diverse clinical indications, including squamous tumors that carry mutant HRAS, as well as in lymphoid, myeloid and solid tumors that do not carry HRAS mutations. Leveraging advances in next-generation sequencing as well as emerging information about cancer genetics and tumor biology, Kura is seeking to identify those patients most likely to benefit from tipifarnib. In November 2018, Kura initiated its first global, registration-directed trial of tipifarnib in patients with recurrent or metastatic HRAS mutant HNSCC