Rashmi Krishna Murthy

Outcomes of children exposed in utero to chemotherapy for breast cancer.

IntroductionThe incidence of breast cancer diagnosed during pregnancy is expected to increase as more women delay childbearing in the United States. Treatment of cancer in pregnant women requires prudent judgment to balance the benefit to the cancer patient and the risks to the fetus. Prospective data on the outcomes of children exposed to chemotherapy in utero are limited for the breast cancer population.MethodsBetween 1992 and 2010, 81 pregnant patients with breast cancer were treated in a single-arm, institutional review board–approved study with 5-fluorouracil, doxorubicin, and cyclophosphamide (FAC) in the adjuvant or neoadjuvant setting. Labor and delivery records were reviewed for each patient and neonate. In addition, the parents or guardians were surveyed regarding the health outcomes of the children exposed to chemotherapy in utero.ResultsIn total, 78% of the women (or next of kin) answered a follow-up survey. At a median age of 7 years, most of the children exposed to chemotherapy in utero were growing normally without any significant exposure-related toxicity or health problems. Three children were born with congenital abnormalities: one each with Down syndrome, ureteral reflux or clubfoot. The rate of congenital abnormalities in the cohort was similar to the national average of 3%.ConclusionsDuring the second and third trimesters, pregnant women with breast cancer can be treated with FAC safely without concerns for serious complications or short-term health concerns for their offspring who are exposed to chemotherapy in utero. Continued long-term follow-up of the children in this cohort is required.Trial registrationClinicalTrials.gov Identifier: NCT00510367. Other Study ID numbers: ID01-193, NCI-2012-01578. Registration date: 31 July 2007.

Phase I study of ONT-380, a HER2 inhibitor, in patients with HER2+-advanced solid tumors, with an expansion cohort in HER2+ Metastatic Breast Cancer (MBC)

Purpose: ONT-380 (ARRY-380) is a potent and selective oral HER2 inhibitor. This Phase I study determined the MTD, pharmacokinetics (PK) and antitumor activity of ONT-380 in HER2-positive advanced solid tumors, with an expansion cohort of patients with HER2+ MBC. Experimental Design: ONT-380 was administered twice daily (BID) in continuous 28-day cycles. After a modified 3+3 dose-escalation design determined the MTD, the expansion cohort was enrolled. PK properties of ONT-380 and a metabolite were determined. Response was evaluated by Response Evaluation Criteria in Solid Tumors (RECIST). Results: Fifty patients received ONT-380 (escalation = 33; expansion = 17); 43 patients had HER2+ MBC. Median prior anticancer regimens = 5. Dose-limiting toxicities of increased transaminases occurred at 800 mg BID, thus 600 mg BID was the MTD. Common AEs were usually Grade 1/2 in severity and included nausea (56%), diarrhea (52%), fatigue (50%), vomiting (40%) constipation, pain in extremity and cough (20% each). 5 patients (19%) treated at MTD had grade 3 AEs (increased transaminases, rash, night sweats, anemia, and hypokalemia). The half-life of ONT-380 was 5.38 hours and increases in exposure were approximately dose proportional. In evaluable HER2+ MBC (n = 22) treated at doses ≥ MTD, the response rate was 14% [all partial response (PR)] and the clinical benefit rate (PR + stable disease ≥ 24 weeks) was 27%. Conclusions: ONT-380 had a lower incidence and severity of diarrhea and rash than that typically associated with current dual HER2/EGFR inhibitors and showed notable antitumor activity in heavily pretreated HER2+ MBC patients, supporting its continued development. Clin Cancer Res; 23(14); 3529–36. ©2017 AACR.

Effect of adjuvant/neoadjuvant trastuzumab on clinical outcomes in patients with HER2-positive metastatic breast cancer

The purpose of the current study was to describe the outcomes of patients with human epidermal growth factor receptor 2 (HER2)‐overexpressed/amplified (HER2+) early breast cancer who received adjuvant or neoadjuvant trastuzumab‐based therapy and were subsequently retreated with trastuzumab for metastatic disease.

T-DM1 Activity in Metastatic Human Epidermal Growth Factor Receptor 2–Positive Breast Cancers That Received Prior Therapy With Trastuzumab and Pertuzumab

Purpose Ado-trastuzumab emtansine (T-DM1) is currently approved for treatment in patients with human epidermal growth factor receptor 2 (HER2)-positive, metastatic breast cancer (MBC) who previously received trastuzumab and a taxane. However, there are no data on the activity of T-DM1 in patients who received prior pertuzumab, which is now included as standard first-line therapy. The goal of this study was to assess the efficacy of T-DM1 in routine clinical practice in a contemporary patient population that received both prior trastuzumab and pertuzumab. Patients and Methods We identified all patients with HER2-positive MBC who received T-DM1 after trastuzumab and pertuzumab between March 1, 2013, and July 15, 2015, via electronic pharmacy records and departmental databases at three institutions: MD Anderson Cancer Center, Smilow Cancer Hospital at Yale, and The James Cancer Hospital at the Ohio State University. We reviewed medical records of each case to confirm treatment sequencing and outcome. Results Of patients, 82 were identified and 78 were available for outcome analysis; 32% received T-DM1 as first- and second-line line therapy, and 48% received it as fourth-line treatment or later. Rate of prolonged duration on therapy, defined as duration on therapy ≥ 6 months, was 30.8% (95% CI, 20.6% to 41.1%), and tumor response rate was 17.9% (95% CI, 9.4% to 26.4%). Median duration on therapy was 4.0 months (95% CI, 2.7 to 5.1; range, 0 to 22.5 months). T-DM1 was discontinued for disease progression in 84% of patients and for toxicity in 10%. Conclusion Tumor response rates were lower than in prior reports of trastuzumab-resistant, HER2-positive MBC, but one third of patients received therapy with T-DM1 for ≥ 6 months, which suggests a clinically relevant benefit in patients who received prior pertuzumab.

Targeting the PI3K/AKT/mTOR pathway for the treatment of mesenchymal triple-negative breast cancer: Evidence from a phase 1 trial of mTOR inhibition in combination with liposomal doxorubicin and bevacizumab

Importance Triple-negative breast cancer (TNBC) classified by transcriptional profiling as the mesenchymal subtype frequently harbors aberrations in the phosphoinositide 3-kinase (PI3K) pathway, raising the possibility of targeting this pathway to enhance chemotherapy response. Up to 30% of mesenchymal TNBC can be classified histologically as metaplastic breast cancer, a chemorefractory group of tumors with a mixture of epithelial and mesenchymal components identifiable by light microscopy. While assays to identify mesenchymal TNBC are under development, metaplastic breast cancer serves as a clinically identifiable surrogate to evaluate potential regimens for mesenchymal TNBC. Objective To assess safety and efficacy of mammalian target of rapamycin (mTOR) inhibition in combination with liposomal doxorubicin and bevacizumab in patients with advanced metaplastic TNBC. Design, Setting, and Participants Phase 1 study with dose escalation and dose expansion at the University of Texas MD Anderson Cancer Center of patients with advanced metaplastic TNBC. Patients were enrolled from April 16, 2009, to November 4, 2014, and followed for outcomes with a cutoff date of November 1, 2015, for data analysis. Interventions Liposomal doxorubicin, bevacizumab, and the mTOR inhibitors temsirolimus or everolimus using 21-day cycles. Main Outcomes and Measures Safety and response. When available, archived tissue was evaluated for aberrations in the PI3K pathway. Results Fifty-two women with metaplastic TNBC (median age, 58 years; range, 37-79 years) were treated with liposomal doxorubicin, bevacizumab, and temsirolimus (DAT) (N = 39) or liposomal doxorubicin, bevacizumab, and everolimus (DAE) (N = 13). The objective response rate was 21% (complete response = 4 [8%]; partial response = 7 [13%]) and 10 (19%) patients had stable disease for at least 6 months, for a clinical benefit rate of 40%. Tissue was available for testing in 43 patients, and 32 (74%) had a PI3K pathway aberration. Presence of PI3K pathway aberration was associated with a significant improvement in objective response rate (31% vs 0%; P = .04) but not clinical benefit rate (44% vs 45%; P > .99). Conclusions and Relevance Using metaplastic TNBC as a surrogate for mesenchymal TNBC, DAT and DAE had notable activity in mesenchymal TNBC. Objective response was limited to patients with PI3K pathway aberration. A randomized trial should be performed to test DAT and DAE for metaplastic TNBC, as well as nonmetaplastic, mesenchymal TNBC, especially when PI3K pathway aberrations are identified.

Impact of adjuvant trastuzumab on outcomes of HER2-positive breast cancer patients treated with HER2-targeted therapy in the metastatic setting.

527 Background: The treatment benefits of epidermal growth factor receptor (EGFR) monoclonal antibodies for patients with KRAS mutations have not been demonstrated. However, some studies have suggested that all KRAS mutations are not equivalent, and that KRAS G13D mutations might have some survival benefit. METHODS We retrospectively analyzed the efficacy and toxicity of treatment with EGFR monoclonal antibody in 8 patients with KRAS G13D mutations and 5-FU/oxaliplatin/irinotecan (CPT) refractory metastatic colorectal cancer compared with 94 KRAS wild type patients at the National Cancer Center Hospital. RESULTS Eight patients with KRAS G13D mutations were treated with anti-EGFR monoclonal antibodies between July, 2009 and July, 2011. The median age was 66 (42-70); male/female 6/2; PS was 0/1/2, 2/5/1; treatment regimen was cetuximab/ cetuximab+CPT/ panitumumab+CPT, 2/5/1. Response rate (RR) was 12.5% and disease control rate (DCR) was 50.0% with 1 PR, 3 SD, and 4 PD. The PR case treated with cetuximab+CPT showed marked regression of tumor and long duration of treatment (9 months). The progression free survival (PFS) of 2 SD cases was 4.2 and 3.9 months. The other SD case is now on treatment. The median PFS of the 8 patients was 2.1 months (95% confidence interval [CI]: 0.0-5.2). The median overall survival (OS) has not been reached. Grade 3/4 toxicities included 1 hypomagnesemia G4 and 1 rash acneiform G3. Meanwhile, 94 KRAS wild type patients treated with anti EGFR monoclonal antibodies had an RR of 22.3% and DCR was 66.0% with 21 PR, 41 SD, 30 PD, and 2 NE. PFS was 5.6 months (95% CI: 4.9-6.3) and OS was 8.6 months (95% CI: 6.5-10.7). CONCLUSIONS In this analysis, we identified one PR to anti-EGFR monoclonal antibody in a patient with KRAS G13D mutation and chemo-refractory metastatic colorectal cancer. However, we were unable to demonstrate equivalent efficacy in patients with KRAS G13D mutations and KRAS wild type patients. Further studies are needed to evaluate the efficacy and prognosis for this treatment.

Tucatinib with capecitabine and trastuzumab in advanced HER2-positive metastatic breast cancer with and without brain metastases: a non-randomised, open-label, phase 1b study

BACKGROUND Tucatinib is a potent and selective oral HER2 tyrosine kinase inhibitor, with the potential to provide a well tolerated new treatment option for patients whose disease has progressed on currently available therapies. We aimed to determine the recommended phase 2 dose, safety, pharmacokinetics, and preliminary activity of tucatinib in combination with capecitabine or trastuzumab in patients with HER2-positive breast cancer with or without brain metastases. METHODS In this non-randomised, open-label, phase 1b trial done in five sites in the USA, we recruited patients aged 18 years or older with HER2-positive progressive breast cancer who had been previously treated with trastuzumab, pertuzumab, and trastuzumab emtansine. Eligible patients required HER2-positivity assessed locally, evaluable lesions as defined per Response Evaluation Criteria in Solid Tumors, version 1.1, and an Eastern Cooperative Oncology Group performance status of 0 or 1. Tucatinib was administered twice a day in conjunction with capecitabine 1000 mg/m2 orally twice a day for 14 days of a 21-day cycle, trastuzumab 6 mg/kg intravenously once every 21 days, or both. A modified 3 + 3 dose-escalation design was used to determine the recommended phase 2 dose, starting with tucatinib in combination with capecitabine or trastuzumab, and subsequently evaluating the triplet combination. The primary endpoint was to establish the maximum tolerated dose and recommended phase 2 dose of tucatinib, evaluated by toxicity assessments. Efficacy was assessed in all patients by contrast CT of the body. Analyses included all patients who had received at least one dose of study treatment. The study is registered with ClinicalTrials.gov, number NCT02025192. FINDINGS Between Jan 15, 2014, and Dec 15, 2015, 60 patients were enrolled and treated. The current report is from mature data as of June 30, 2017. The tucatinib recommended phase 2 dose was determined to be 300 mg orally twice a day, equivalent to single-agent maximum tolerated dose. Pharmacokinetic analysis showed that there was no drug-drug interaction with capecitabine. Adverse events seen at the recommended phase 2 dose regardless of causality, grade, and treatment group included diarrhoea (35 [67%] of 52 patients), nausea (31 [60%] patients), palmar-plantar erythrodysaesthesia syndrome (23 [44%] patients), fatigue (20 [38%] patients), and vomiting (20 [38%] patients). In all patients, treatment-related toxicities of grade 3 and worse included fatigue (five [8%] patients), diarrhoea (four [7%] patients), and palmar-plantar erythrodysaesthesia (four [7%] patients). No treatment-related deaths were reported. The proportion of patients with measurable disease achieving objective response was 83% (five of six patients) in the combination of tucatinib with capecitabine, 40% (six of 15 patients) in the combination of tucatinib with trastuzumab, and 61% (14 of 23 patients) in the combination of tucatinib with both capecitabine and trastuzumab. INTERPRETATION Tucatinib in combination with capecitabine and trastuzumab had acceptable toxicity and showed preliminary anti-tumour activity. Validation of the current study results will be determined in the double-blinded randomised study, HER2CLIMB (ONT-380-206; NCT02614794). FUNDING Cascadian Therapeutics, a wholly owned subsidiary of Seattle Genetics.

Abstract P4-14-19: ONT-380 in the treatment of HER2+ breast cancer central nervous system (CNS) metastases (mets)

Background: The risk of CNS involvement in patients with HER2+ metastatic breast cancer (MBC) is high. The natural history of HER2+ CNS metastases (mets) is different from other breast cancer subtypes; there is a longer time from metastatic diagnosis to CNS relapse, greater control of extracranial disease at the time of CNS relapse, and longer median overall survival from the time of CNS relapse. Local treatments, i.e., surgery and/or radiation, remain the mainstay of treatment for HER2+ CNS disease as standard systemic therapy options have limited efficacy. ONT-380, a potent HER2 selective tyrosine kinase inhibitor with minimal EGFR-like side effects, has been associated with increased survival compared to lapatinib or neratinib in an animal model of HER2+ CNS disease. Here, we describe 24 pts from two studies with response-evaluable CNS mets treated with ONT-380 in combination with other systemic therapies. Methods: Pts with asymptomatic untreated or post-treatment progressive CNS mets were enrolled in ongoing phase 1b studies of ONT-380 + ado-trastuzumab emtansine (T-DM1) or ONT-380 ± trastuzumab (T) ±capecitabine (C). All pts received treatment in 21 day cycles including ONT-380 300 mg PO BID and approved doses of either T-DM1, T or C alone, or T+C. Eligibility criteria for all pts included prior treatment with T and a taxane, and for pts receiving T and/or C, prior T-DM1. Prior lapatinib was allowed. Assessments included safety, systemic tumor response per RECIST 1.1, and CNS tumor response by MRI every 2 cycles per modified RECIST 1.1. Results: 24 pts (10 with untreated CNS mets and 14 with progressive CNS mets after local therapy) received ONT-380 plus T-DM1 (n =14), C (n=1), T (n = 5) or T+C (n = 4) for 1-8 cycles. Of these 24 pts, 14 are evaluable for response in the CNS (at least one follow-up MRI); 7 pts have not yet been rescanned, and 3 are non-evaluable. In the 14 response-evaluable pts, best CNS response has been: 1 CNS CR (T-DM1), 4 CNS PR (T-DM1 n = 2; T+C n = 1; C n=1) and 9 CNS SD (T-DM1 n = 5; T n = 3; T+C n=1). Pts with CR or PR (prior lapatinib n=2; prior pertuzumab n=2; prior T-DM1 n=2) all had > 50% decrease in CNS target lesions. One CNS non-evaluable pt (T) had a 15% increase in their target lesion and underwent surgical resection; pathology, however, revealed no viable tumor with only necrotic tissue present. Two additional CNS non-evaluable pts (T-DM1 n=1; C+T n=1) were taken off study due to systemic PD after treatment was held for AEs (Gr 3 AST/ALT elevation [n=1]; Gr 4 edema in thalamic lesion [n=1]). No other ≥ Gr 3 ONT-380 related events were reported. Systemic disease control was also seen, with a best response in 17 evaluable pts of 6 PR, 9 SD, and 2 PD. Conclusions: This case series demonstrates early clinical signs of activity of ONT-380 against HER2+ CNS mets in combination with other systemic agents. Further study of the CNS activity of ONT-380 is ongoing and further studies are being planned. Updated results will be reported. Clinical trial information: NCT01983501, NCT02025192. Citation Format: Murthy RK, Hamilton E, Borges VF, Moulder S, Aucoin N, Welch S, Chaves J, Falkson CI, Walker L, Ferrario C. ONT-380 in the treatment of HER2+ breast cancer central nervous system (CNS) metastases (mets). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-14-19.

Long‐Term Survival of De Novo Stage IV Human Epidermal Growth Receptor 2 (HER2) Positive Breast Cancers Treated with HER2‐Targeted Therapy

BACKGROUND An increasing proportion of human epidermal growth receptor 2 (HER2) positive (HER2+) metastatic breast cancer (MBC) is diagnosed as de novo stage IV disease. We hypothesize that a subset of these patients who achieve no evidence of disease (NED) status after multimodality HER2-targeted treatments may have prolonged progression-free survival (PFS) and overall survival (OS). MATERIALS AND METHODS Patients with de novo stage IV, HER2+ MBC (n = 483) diagnosed between 1998 and 2015 were identified at two institutions (Yale and MD Anderson Cancer Centers). Clinical variables, treatment details, and survival outcomes were compared between those who achieved NED and those who did not. RESULTS All patients received trastuzumab, and 20% also received pertuzumab as first-line therapy. The median OS was 5.5 years (95% confidence interval [Cl]: 4.8-6.2). Sixty-three patients (13.0%) achieved NED; their PFS and OS rates were 100% and 98% (95% CI: 94.6%-100%), respectively, at 5 years and remained the same at 10 years. For patients with no NED (n = 420), the PFS and OS rates were 12% (95% CI: 4.5%-30.4%) and 45% (95% CI: 38.4%-52.0%) at 5 years and 0% and 4% (95% CI, 1.3%-13.2%) at 10 years, respectively. NED patients more frequently had solitary metastasis (79% vs. 51%, p = .005) and surgery to resect cancer (59% vs. 22%, p ≤ .001). In multivariate analysis, NED status (hazard ratio [HR]: 0.014, p = .0002) and estrogen receptor positive status (HR: 0.72; p = .04) were associated with prolonged OS. CONCLUSION Among patients with de novo stage IV, HER2+ MBC, those who achieve NED status have a very high PFS and OS. Further randomized studies are required to fully understand the impact of systemic or locoregional therapy on achieving these excellent long-term outcomes. IMPLICATIONS FOR PRACTICE In this retrospective review at two institutions, it was demonstrated that 13% of patients with de novo stage IV, human epidermal growth receptor 2 positive metastatic breast cancer achieved no evidence of disease (NED) status with trastuzumab-based therapy plus/minus local therapies, and these patients had a very high progression-free survival (100%) and overall survival (98%) at both the 5- and 10-year time points. Achieving NED status may be an important therapeutic goal. However, further randomized studies are required to fully understand the impact of systemic or locoregional therapy on achieving these excellent long-term outcomes.

Genetic Counseling Referral Rates in Long-Term Survivors of Triple-Negative Breast Cancer

Background: Inherited BRCA gene mutations (pathogenic variants) cause 10% of breast cancers. BRCA pathogenic variants predispose carriers to triple-negative breast cancer (TNBC); around 30% of patients with TNBC carry BRCA pathogenic variants. The 2018 NCCN Guidelines for Genetic/Familial High-Risk Assessment: Breast and Ovarian recommend genetic counseling referrals for patients with TNBC diagnosed at age ≤60 years. This study sought to describe genetic counseling referral patterns among long-term TNBC survivors at The University of Texas MD Anderson Cancer Center. Methods: This single-institution retrospective analysis of female long-term (disease-free for ≥5 years) TNBC survivors sought to determine the rate of genetic counseling referral among patients diagnosed at age ≤60 years between 1992 and 2008. Patients who underwent treatment and surveillance visits at our institution and were followed until 2017 were included. We collected BRCA pathogenic variant status among tested patients. Descriptive statistical methods and a univariate analysis were used to identify patient characteristics associated with genetic counseling referral. Results: We identified 646 female long-term TNBC survivors with a median age at diagnosis of 47 years. Of these, 245 (38%) received a recommendation for a genetic counseling referral. Among those referred, 156 (64%) underwent genetic testing, and 35% of those tested had BRCA pathogenic variants. Interestingly, among those referred, 20% declined genetic testing. The rate of genetic referrals improved over time, from 25% among TNBC survivors whose last surveillance visit was between 2011 and 2013 to 100% among those whose last surveillance visit was between 2014 or later. Younger age and premenopausal status at diagnosis and a family history of breast or ovarian cancer were associated with an increased rate of referral for genetic counseling. Conclusions: Among long-term TNBC survivors, the rate of referral to genetic counseling increased over time, and among those tested, 35% carried a BRCA pathogenic variant. Survivorship care provides an excellent opportunity to refer eligible patients for genetic counseling.