Patient-reported treatment toxicity and adverse events in Black and White women receiving chemotherapy for early breast cancer

PURPOSE

It is not known whether chemotherapy-related symptom experiences differ between Black and White women with early breast cancer (Stage I-III) receiving current chemotherapy regimens and, in turn, influences dose delay, dose reduction, early treatment discontinuation, or hospitalization.

METHODS

Patients self-reported their race and provided symptom reports for 17 major side effects throughout chemotherapy. Toxicity and adverse events were analyzed separately for anthracycline and non-anthracycline regimens. Fisher's exact tests and two-sample t-tests compared baseline patient characteristics. Modified Poisson regression estimated relative risks of moderate, severe, or very severe (MSVS) symptom severity, and chemotherapy-related adverse events.Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary.no changes RESULTS: In 294 patients accrued between 2014 and 2020, mean age was 58 (SD13) and 23% were Black. For anthracycline-based regimens, the only significant difference in MSVS symptoms was in lymphedema (41% Black vs 20% White, p = .04) after controlling for axillary surgery. For non-anthracycline regimens, the only significant difference was MSVS peripheral neuropathy (41% Blacks vs. 23% White) after controlling for taxane type (p = .05) and diabetes (p = .05). For all other symptoms, severity scores were similar. Dose reduction differed significantly for non-anthracycline regimens (49% Black vs. 25% White, p = .01), but not for anthracycline regimens or in dose delay, early treatment discontinuation, or hospitalization for either regimen.

CONCLUSION

Except for lymphedema and peripheral neuropathy, Black and White patients reported similar symptom severity during adjuvant chemotherapy. Dose reductions in Black patients were more common for non-anthracycline regimens. In this sample, there were minimal differences in patient-reported symptoms and other adverse outcomes in Black versus White patients.

Abstract P1-17-03: Statin use, site of recurrence, and survival among post-menopausal women taking bisphosphonates as adjuvant therapy for breast cancer (SWOG S0307)

Purpose: Statins may mediate suppression of molecular pathways conferring benefit in cancer. Statins have shown anti-tumor effects in preclinical studies and have been associated with decreased recurrence and improved disease-specific survival. While designed to target cholesterol biosynthesis, statins can also have liver, bone and brain effects. We collected data on statin use in the S0307 adjuvant bisphosphonate trial to test the hypothesis that statin use may decrease risk of recurrence to liver, bone and brain as well as second primary (contralateral) breast cancers, and may act synergistically with bisphosphonates to decrease the risk of recurrence to bone.

Patients and Methods: In S0307, 6097 patients diagnosed with Stage I-III breast cancer who had undergone surgery and were receiving adjuvant systemic therapy were randomized to receive zoledronic acid, clodronate, or ibandronate for 3 years. No significant difference was found in disease-free survival (DFS) among the 3 groups, including a sub-analysis of patients > age 55. Statin use was infrequent in younger women in S0307, consequently we analyzed statin use in those > age 55. Cox proportional hazard models were used to determine which variables were independently associated with DFS and to estimate hazard ratios (HR) and 95% confidence intervals (CI).

Results: Among women aged ≥ 55 years, 684 (27%) reported taking a statin at baseline and 1,848 did not. Both groups were similar in terms of hormone receptor and HER2 status (p = 0.82). Median age in the statin group was 64.3 versus 61.0 years in the no statin group, mean BMI 31.2 v. 29.5, mean tumor size 2.1cm v. 2.3cm, negative lymph nodes 60% v. 54%, Stage I disease 47% v. 36%, and receipt of chemotherapy 62% v. 71% (all p < 0.01). In the statin group, 122 (17.8%) experienced a DFS event compared to 313 (16.9%) in the no statin group (HR 1.18, CI 0.95-1.46). No difference was observed by statin use in overall recurrence (p=0.28), distant recurrence (p=0.64), or recurrences to the bone (p=0.64), liver (p=0.38) or brain (p=0.65) at initial recurrence. There was no synergy between statin use and specific bisphosphonates.

Recurrence and statin useOutcomeGroup 1: On stan at baseline n=684Group 2: No statin at baseline n=1848DFS events122 (17.8%)313 (16.9%)Died without recurrence51 7.5%)97 (5.2%)Recurrence71 (10.4%)216 (11.7%)Contralateral breast cancer9 (1.3%)17 (0.9%)Distant recurrence48 (7%)157 (8.5%)Bone as 1st site of distant recurrence (% distant recurrence)31 (65%)76 (48%)Liver as 1st site of distant recurrence (% distant recurrence)6 (13%)24 (16%)Brain/CNS as 1st site of distant recurrence (% distant recurrence)5 (10%)17 (11%)

Conclusions: We found no evidence that statins reduce risk of second primary breast cancers or distant metastases among post-menopausal women with early-stage breast cancer. Despite promising preclinical data, they did not appear to act in synergy with a specific bisphosphonate. Though women in the statin group had less advanced disease at study entry, statin use was not associated with improved DFS. Results are limited by lack of information about type of statin used, adherence, or initiation of statin in control group.

Citation Format: Kizub D, Miao J, Stopeck A, Thompson P, Paterson AH, Clemons M, Dees EC, Ingle JN, Falkson CI, Barlow W, Hortobagyi GN, Gralow JR. Statin use, site of recurrence, and survival among post-menopausal women taking bisphosphonates as adjuvant therapy for breast cancer (SWOG S0307) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-17-03.

Abstract GS4-07: Race, ethnicity and clinical outcomes in hormone receptor-positive, HER2-negative, node-negative breast cancer: results from the TAILORx trial

Background: Black race is associated with worse outcomes in localized hormone receptor (HR)-positive breast cancer in population-based and in clinical trial cohorts, whether using self-identified race (Albain et al. JNCI 2009 [PMID: 19584328; Sparano et al. JNCI 2012 [PMID: 22250182) or genetically-identified race (Schneider et al. J Precision Oncol 2017 [PMID: 29333527]). This disparity persists after adjustment for treatment delivery parameters (Hershman et al. JCO 2009 [PMID:19307504]). We evaluated clinicopathologic characteristics, treatment delivered and clinical outcomes in the Trial Assigning Individualized Options for Treatment (TAILORx) by race and ethnicity (Sparano et al. NEJM 2018 [PMID: 29860917]).

Methods: The analysis included 9719 evaluable TAILORx participants. The association between clinical outcomes and race (white, black, Asian, other/unknown) and ethnicity (Hispanic vs. non-Hispanic) was examined, including invasive disease-free survival (iDFS), distant relapse-free interval (DRFI), relapse-free interval (RFI), and overall survival (OS). Proportional hazards models were fit including age (5 categories), tumor size (>2 cm vs. <=2 cm), histologic grade (high vs. medium vs. low vs. unknown), continuous recurrence score (RS), race, and ethnicity in the overall population and randomized treatment arms in the RS 11-25 cohort.

Results: The study population included 8189 (84%) whites, 693 (7%) blacks, 405 (4%) Asians, and 432 (4%) with other/unknown race. Regarding ethnicity, 7635 (79%) were non-Hispanic, 889 (9%) Hispanic, and 1195 (12%) unknown. There was no significant difference in RS distribution (p=0.22) in blacks compared with whites, or in median (17 vs. 17) or mean RS (19.1 vs. 18.2). There was likewise no difference in Hispanic vs. non-Hispanic ethnicity for RS distribution (p=0.72) or median (17 vs. 17) or mean RS (18.5 vs. 18.0). Black race (39% vs. 30%) and Hispanic ethnicity (39% vs. 30%) were both associated with younger age (</=50 years) at diagnosis. The use and type of adjuvant chemotherapy and endocrine therapy, and duration of endocrine therapy, were similar in black (vs. white) and Hispanic (vs. non-Hispanic) populations. In proportional hazards models, black race (compared with white race) was associated with worse clinical outcomes in the entire population and in those with a RS 11-25 (see table). Hispanic ethnicity was generally associated with better outcomes (compared with non-Hispanic ethnicity). For the cohort with a RS of 11-25, there was no evidence for chemotherapy benefit for any racial or ethnic group.

Race (black vs.white) and clinical outcomes in proportional hazards modelsClinical endpointEntire Population (N=693 black) Hazard ratio for eventRS 11-25 (N=471 black) Hazard ratio for eveniDFS1.33 (p=0.005)1.49 (p=0.001)DRFI1.21 (p=0.28)1.60 (p=0.02)RFI1.39 (p=0.02)1.80 (p<0.001)OS1.52 (p=0.005)1.67 (p=0.003

Conclusions: In patients eligible and selected for participation in TAILORx, black women had worse clinical outcomes despite similar 21-gene assay RS results and comparable systemic therapy. This adds to an emerging body of evidence suggesting a biologic basis or other factors contributing to racial disparities in HR-positive breast cancer that requires further evaluation.

Citation Format: Albain K, Gray RJ, Sparano JA, Makower DF, Pritchard KI, Hayes DF, Geyer, Jr. CE, Dees EC, Goetz MP, Olson, Jr. JA, Lively T, Badve SS, Saphner TJ, Wagner LI, Whelan TJ, Ellis MJ, Paik S, Wood WC, Ravdin PM, Keane MM, Gomez HL, Reddy PS, Goggins TF, Mayer IA, Brufsky AM, Toppmeyer DL, Kaklamani VG, Berenberg JL, Abrams J, Sledge, Jr. GW. Race, ethnicity and clinical outcomes in hormone receptor-positive, HER2-negative, node-negative breast cancer: results from the TAILORx trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr GS4-07.

Correction to: Measuring and understanding adherence in a home-based exercise intervention during chemotherapy for early breast cancer

In the original publication, the sixth author name was published incorrectly as A. Wood. The correct author name should read as W. A. Wood.

Abstract OT2-07-06: Phase Ib study to assess the safety, tolerability, and clinical activity of gedatolisib in combination with palbociclib and either letrozole or fulvestrant in women with metastatic or locally advanced/recurrent breast cancer (B2151009)

Background:Hormone receptor positive (HR+) disease is the most common subset of advanced breast cancer (BC). The majority of women with HR+ metastatic BC (MBC) develop resistance to endocrine therapy (ET), with a median survival of 2-3 years. A new strategy to treat HR+ MBC involves the combination of ET and a cyclin-dependent kinase 4/6 inhibitor (CDKi 4/6), which has demonstrated improved progression-free survival (PFS) in both first-and later-line MBC. Preclinical evidence in PI3K-mutant cell-line xenografts demonstrated that combinations of PI3K and CDK4/6i reduced intrinsic and adaptive resistance to ET, leading to tumor regression (Vara, 2004; Pfizer data). Inhibition of the PI3K/mTOR pathway by gedatolisib (G) may provide a new therapy to overcome ET resistance. These findings support developing the triplet combination of G with the CDKi 4/6 palbociclib (P)+letrozole (L) or fulvestrant (F) for the treatment of patients (pts) with ER+/HER2- BC.

Methods: This ongoing study in women with ER+/HER2- MBC, in first- and later-line settings, includes a dose-escalation (DE) to evaluate dose-limiting toxicities (DLTs, primary endpoint [pEP]) and determine the maximum tolerated dose and recommended phase 2 dose (RP2D) for a triplet regimen of G+P+L or G+P+F. The escalation rules follow the modified toxicity probability interval method (G doses: 180 and 215 mg IV weekly). Treatment assignment to the triplet is based on investigator decision and bone-only disease is permitted. After RP2D determination for each triplet, a 3-arm expansion for early signs of efficacy (ESOE) will investigate objective response rate (ORR) compared to historical controls [pEP] of Arm A) G+P+L in first-line, B) G+P+F in pts with no prior CDKi 4/6 in second-line and C) G+P+F in pts who have received prior CDKi 4/6. Pts receive G+P (125 mg oral daily for 21 days [D] on and 7 D off) + L (2.5 mg oral daily) or F (500 mg IM on D1, 15 of cycle [C] 1; D1 of C2 and then 500 mg IM on D1 of all 28-D cycles). Secondary endpoints include safety, tumor response (DE), PFS (ESOE), pharmacokinetics (PK), and biomarker correlations associated with the PI3K/mTOR pathway.

Results: 27 pts received G (180 mg/week) in combination with P+L (L cohort, n=12) or P+F (F cohort, n=15). Median prior therapies were: L cohort: 1 (range: 0-4); F cohort: 2 (range 1-5). The 3 most common, drug-related adverse events (%) were in L cohort: nausea (75), neutropenia (67), and stomatitis (67); F cohort: stomatitis (67), nausea (60), and neutropenia (53). C1 DLTs were: L cohort: grade (gr) 3 neutropenia (n=1); F cohort: gr 3 stomatitis (n=1). Preliminary rates of stable disease/partial response were: L cohort: 33%/16%; F cohort: 40%/13%. PK parameters and next-generation sequencing of PI3K-related mutations are pending.

Conclusions: G can be combined with P+L or P+F with manageable toxicity and promising preliminary antitumor activity, even in heavily pretreated pts. Dose escalation, followed by expansion for ESOE, is ongoing.

This study is sponsored by Pfizer. Editorial support was provided by Engage Scientific Solutions and was funded by Pfizer.

Citation Format: Forero A, Han HS, Dees EC, Wesolowski R, Bardia A, Kabos P, Kern KA, Perea R, Pierce KJ, Houk B, Rugo HS. Phase Ib study to assess the safety, tolerability, and clinical activity of gedatolisib in combination with palbociclib and either letrozole or fulvestrant in women with metastatic or locally advanced/recurrent breast cancer (B2151009) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT2-07-06.

Measuring and understanding adherence in a home-based exercise intervention during chemotherapy for early breast cancer

PURPOSE

Ensuring and measuring adherence to prescribed exercise regimens are fundamental challenges in intervention studies to promote exercise in adults with cancer. This study reports exercise adherence in women who were asked to walk 150 min/week throughout chemotherapy treatment for early breast cancer. Participants were asked to wear a Fitbit^TM throughout their waking hours, and Fitbit steps were uploaded directly into study computers.

METHODS

Descriptive statistics are reported, and both unadjusted and multivariable linear regression models were used to assess associations between participant characteristics, breast cancer diagnosis, treatment, chemotherapy toxicities, and patient-reported symptoms with average Fitbit steps/week.

RESULTS

Of 127 women consented to the study, 100 had analyzable Fitbit data (79%); mean age was 48 and 31% were non-white. Mean walking steps were 3956 per day. Nineteen percent were fully adherent with the target of 6686 steps/day and an additional 24% were moderately adherent. In unadjusted analysis, baseline variables associated with fewer Fitbit steps were: non-white race (p = 0.012), high school education or less (p = 0.0005), higher body mass index (p = 0.0024), and never/almost never drinking alcohol (p = 0.0048). Physical activity variables associated with greater Fitbit steps were: pre-chemotherapy history of vigorous physical activity (p = 0.0091) and higher self-reported walking minutes/week (p < 0.001), and higher outcome expectations from exercise (p = 0.014). Higher baseline anxiety (p = 0.03) and higher number of chemotherapy-related symptoms rates "severe/very severe" (p = 0.012) were associated with fewer steps. In multivariable analysis, white race was associated with 12,146 greater Fitbit steps per week (p = 0.004), as was self-reported walking minutes prior to start of chemotherapy (p < 0.0001).

CONCLUSIONS

Inexpensive commercial-grade activity trackers, with data uploaded directly into research computers, enable objective monitoring of home-based exercise interventions in adults diagnosed with cancer. Analysis of the association of walking steps with participant characteristics at baseline and toxicities during chemotherapy can identify reasons for low/non-adherence with prescribed exercise regimens.

Abstract P1-12-08: The incidence and outcomes of brain metastases in HER2-positive metastatic breast cancer with the advent of modern anti-HER2 therapies

Background: Human epidermal growth factor receptor 2 (HER2) is over-expressed in approximately 20 - 30% of breast cancers. HER2-positive breast cancers frequently metastasize to the brain. In recent years, many new drugs have been approved for HER2-positive metastatic breast cancer (MBC). In the metastatic setting, trastuzumab was approved in 2000, lapatinib 2007, and pertuzumab and ado-trastuzumab emtansine in 2012. We sought to describe the incidence, time course, and prognostic factors of BM in patients (pts) with HER2+ MBC during the time when dramatic changes in systemic therapy occurred.

Patients/methods: The study included pts with HER2-positive MBC treated at two academic hospitals: Dana Farber Cancer Institute (DFCI) (2000-2007 [DFCI-T1], 2008-2011 [DFCI-T2]) and University of North Carolina (UNC) (2012-2014). We examined the incidence of BM (at diagnosis [dx] and within 1-2 years of MBC dx). We combined the two cohorts to examine outcomes – time to BM, survival following MBC, and survival following BM – using the Kaplan Meier method and Cox regression modeling.

Results: We identified 185 (DFCI n=128, 97 diagnosed 2000-2007 and 31 diagnosed 2008-2011; UNC n=57, all diagnosed 2012-2014) pts with HER2-positive MBC. Through a median of 4 years follow-up after the MBC dx (min 2, max 11), 118 had died and 67 were censored. The median age at MBC dx was 52 (min 25, max 88), 149 (82%) were Caucasian, 88 (48%) had hormone receptor (HR) positive BC, and 67 (37%) had de-novo (i.e., non-recurrent) MBC. BM was present at the MBC dx for 8% of pts in DFCI-T1, 16 % of pts in DFCI-T2, and 16% of pts at UNC. Within 1 year of the MBC dx, BM was present in 21% of DFCI-T1, 29% in DFCI-T2, 23% of UNC pts. Within 2 years of the MBC dx, 67 (36%) pts had developed BM, of which one third (22) were diagnosed at initial MBC presentation. In unadjusted analyses, there were no differences in time to BM dx by age (p=0.2), race (p=0.1) or HR status (p=0.1). The median survival following the development of BM for all pts was 1.5 years. A multivariable model predicting survival after the MBC dx, found factors associated with shorter survival included having (vs. not having) BM at the initial MBC dx, having received (vs. not having received) adjuvant HER2-directed therapy prior to the MBC dx, and having recurrent (vs. de novo) MBC (P≤0.02 for all). Age, HR status, race and time period of MBC dx were not significant in the multivariable model.

Conclusions: Among pts diagnosed in the modern era, after new therapies became available, BM remains a common problem for pts with HER2-positive MBC. While no obvious trends in the incidence of HER2-positive MBC are suggested, conclusions regarding incidence trends should be considered hypothesis-generating until larger, population-based data become available. Nevertheless, a dx of BM early in the course of MBC treatment and prior receipt of adjuvant trastuzumab appeared to confer a more aggressive disease course. Coordinated, prospective collection of the incidence and outcomes of BM among pts with HER2-positive MBC, studies of pts who develop BM &gt;2 years after their MBC dx, and clinical trials of treatment strategies for pts with trastuzumab-resistant BM are needed.

Citation Format: Strulov Shachar S, Deal AM, Vaz-Luis I, Dees EC, Carey LA, Hassett MJ, Garrett AL, Benbow JM, Hughes ME, Mounsey L, Lin N, Anders CK. The incidence and outcomes of brain metastases in HER2-positive metastatic breast cancer with the advent of modern anti-HER2 therapies [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-12-08.

Abstract P1-05-20: Comparing the frequency and types of genetic aberrations between older and younger women with metastatic breast cancer at the University of North Carolina at Chapel Hill

Background: Targeted therapies have the potential to revolutionize cancer treatment in older adults as they are often oral, convenient, may be better tolerated than cytotoxic chemotherapy, and can be tailored to an individual's biomarker profile. We explore the frequency and distribution of potentially actionable genomic alterations among older (≥65) and younger (&lt;65) patients (pts) with metastatic breast cancer (MBC).

Method: Next generation genetic sequencing (UNCseq™) of a dynamic panel of target genes was prospectively offered to pts with MBC treated at the University of North Carolina at Chapel Hill (UNC). DNA libraries were prepared separately from a retrieved archival FFPE tumor sample and a matched normal sample from each pt. Relevant targets were enriched by custom Agilent SureSelect hybrid capture baits using standard protocols. Samples were sequenced on Illumina HiSeq 2000/2500 platforms. Mutational findings were reviewed by a molecular tumor board; variants identified to be potentially actionable underwent confirmatory testing in a CLIA approved laboratory. Confirmed findings were inserted into the pt's EMR accessible by both the pt and the treating oncologist. Two-sided Fisher's exact test was used to compare percentages between age-specific groups.

Results: As of 3/31/16, results were available for 140 pts. 19% were 65 years or older. Breast cancer clinical subtypes were: HR+/HER2- 49%, HER2+ (HR any) 17%, TN 34% and metastatic location was: bone only 5%, visceral only 44%, bone & visceral 51%; no significant differences were observed between older and younger age groups. Older pts were more likely to be Caucasian compared to younger patients (92% v 75%, p=0.06). Overall, older patients had a higher total number of mutations compared to younger patients (see Table) (p=0.04). Mutation types were similar between age groups, although a trend for more PIK3CA mutations among older patients was seen (37% v 20%, p=0.07).

Observed Mutations by Age. ≥ 65 years (%) N=27&lt; 65 years (%) N=113pNumber of Mutations   01127.0414849.0423320.04374.04Type of mutation   PIK3CA3720.07CCND179.99NF-1115.37FGFR144.99PTEN49.69EGFR04.99

Conclusion: Genomic alterations may allow therapeutic tailoring in both older and younger patients with breast cancer. In this cohort with metastatic disease, older patients had significantly more mutations, but no clear difference in mutational types was seen by age. The relative small number of older pts in this cohort limits generalization, but supports the need for more extensive characterization of molecular aberrations among older pts with metastatic breast cancer in the new era of targeted therapy.

Research support by the University Cancer Research Fund, NCI Breast Cancer SPORE grant (CA58223), John A. Hartford Foundation and Susan G. Komen Foundation.

Citation Format: Jolly TA, Grilley-Olson JE, Deal AM, Ivanova A, Hayward MC, Benbow JM, Parker JS, Patel NM, Eberhard DA, Weck KE, Mieczkowski P, Dees EC, Muss HD, Reeder-Hayes KE, Earp HS, Sharpless NE, Carey LA, Hayes DN, Anders CK. Comparing the frequency and types of genetic aberrations between older and younger women with metastatic breast cancer at the University of North Carolina at Chapel Hill [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-05-20.

Abstract PD6-07: Genomic sequencing in metastatic breast cancer patients to inform clinical practice at the University of North Carolina at Chapel Hill

Background: An increasing number of molecularly-targeted therapies for metastatic breast cancer (MBC) are clinically-available (approved and investigational). These anti-cancer agents target specific molecular abnormalities such as mutated, amplified, deleted, or rearranged genes. Reporting of unique tumor genetic alterations is not included in routine clinical/diagnostic panels. In MBC, knowledge of mutational status may foster efficient transitions in clinical care and trial enrollment at disease progression. We describe the development and implementation of a clinically-integrated genomic sequencing program and report how information regarding targetable genomic aberrations in MBC patients (pts) is used to improve clinical practice in an academic setting.

Methods: Genomic sequencing of investigative biomarkers was prospectively offered to pts with MBC. DNA libraries were prepared separately from a retrieved archival FFPE tumor sample and a matched normal sample from each pt. Relevant targets were enriched by custom Agilent SureSelect hybrid capture baits using standard protocols. Samples were sequenced on Illumina HiSeq 2000/2500 platforms. Mutational findings were reviewed by a molecular tumor board (MTB); variants identified to be potentially actionable underwent confirmatory testing in a CLIA-approved laboratory. Confirmed findings were inserted into the pt's EMR accessible by both the pt and the treating oncologist.

Results: Of the 725 MBC pts seen at UNC since 1/1/2012, 194 (27%) contributed samples for genomic sequencing. Of those whose tumors were sequenced, average age at MBC diagnosis was 54 (25 - 91); 73% were Caucasian, 16% African American. De novo MBC accounted for 39 (20%) sequenced pts. Of sequenced patients, sites of metastatic disease included bone only (7%), visceral only (46%), and both bone and visceral (47%). Approximately 1/3 of pts were consented for sequencing at time of initial MBC diagnosis, 1/4 after 1st line therapy for MBC, and the remaining at or beyond their 2nd line. In total, 131 (68%) pts have sequencing results available of which 43% of pts had reportable mutations deemed actionable by the MTB. Specific mutations and observed frequency by subtype are shown below. Pts (19%) whose tumors were sequenced were more commonly enrolled in a therapeutic clinical trial for MBC, a higher rate than seen in the non-sequenced group (7%) (p&lt;0.001). To date, 27% of pts' tumors harbored an alteration that is an eligibility requirement for a molecularly-targeted therapeutic trial accruing pts at UNC.

Observed Mutation by Clinical Subype Genes Total # (56 pts)HR+/HER2- (25 pts)HER2+ (13 pts)TNBC (18pts)PIK3CA15933TP5315456CCND19531NF-14103FGFR13300PTEN3012KRAS2011MDM22110PIK3R12002ROS12011TSC12011Other*14518TOTAL73281728*Mutations observed only once

Conclusion: Preemptive genomic sequencing can be integrated into the clinical and operational practice of a comprehensive cancer center. Currently this research tool and program provides valuable information that has the potential to foster both clinical trial eligibility and/or enrollment. With longer follow-up, we hope such an approach ultimately will improve patient outcomes.

Citation Format: Grilley-Olsen J, Keith KC, Hayward M, Dees EC, Deal A, Ivanova A, Benbow JM, Parker J, Patel NM, Eberhard D, Mieczkowski P, Weck KE, Hayes DN, Muss H, Jolly T, Reeder-Hayes K, Earp HS, Sharpless N, Carey L, Anders CK. Genomic sequencing in metastatic breast cancer patients to inform clinical practice at the University of North Carolina at Chapel Hill. [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 PD6-07.

Abstract P2-16-13: Phase I dose escalation clinical trial of the PI3K inhibitor BKM120 and capecitabine (C) in metastatic breast cancer (MBC)

Background: PIK3CA is one of the most frequently mutated genes in human breast cancer, and the high expression of a PIK3CA-pathway signature is associated with the poor prognosis Luminal B and Basal-like expression subtypes. BKM120 is an oral pan-class I phosphatidylinositol-3-kinase (PI3K) inhibitor, which has shown activity in preclinical and early clinical testing, and synergy with both endocrine and chemotherapy. In this trial we sought to evaluate the safety and estimate the maximum tolerated dose (MTD) of the combination of BKM120 and C in patients (pts) with MBC.

Methods: In a 3+3 dose escalation design, we evaluated four cohorts of BKM 120 daily plus C BID x 14 days in 21 day cycles. Standard definitions for DLT and MTD were used and evaluated on the first cycle. Toxicity was graded by CTCAE version 4. Response was evaluated after 2 cycles by RECIST criteria. Pts with MBC appropriate for treatment with C who had &lt;4 prior chemotherapy regimens and normal organ, bone marrow and cardiac parameters were eligible.

Results: 21 pts (11 hormone receptor (HR)+, 3 HER2+, 9 HR/HER2-negative) were enrolled and treated. All were evaluable for toxicity and 14 for response to date. Median age was 54 (range 35-65). Median prior chemotherapy regimens for MBC was 2 (range 1-4). The following dose levels (DL) were evaluated: BKM120 50 mg/d + C 1000 mg/m2/BID x 14(DL 1-4 pts), BKM120 80 mg/d + C 1000 mg/m2/BID x 14 (DL2-3 pts), BKM120 100 mg/d + C 1000 mg/m2/BID x 14 (DL3-9 pts), BKM120 100 mg/d + C 1250 mg/m2/BID x 14 (DL4-5 pts). Most frequent adverse events (all grades) included: Nausea (12), mood disorders (11), PPE (9), diarrhea (8), fatigue (7), vomiting (5) mucositis (4), rash (4), photosensitivity (3), hyperglycemia (3). Grade 3 or higher AEs in any cycle were transaminitis (3) diarrhea (2) mood disorder (2), hyperglycemia, fatigue, photosensitivity, PPE (1 pt each). DLTs: grade 3 hyperglycemia (1/6 pts at DL3), and grade 3 mood disorder in 1/5 pts DL 4. Additionally 4 of 5 patients at DL 4 required dose reduction or delay prior to C3D1. Thus DL 4 exceeded the MTD and DL 3 was expanded for further safety evaluation. Antitumor activity was seen with best responses of 1 CR (at DL 3), 3 PR (DL1 and 4) and 7 SD.

PK analysis, assessment of tumor PIK3CA mutation status and intrinsic subtype by PAM50 is ongoing.

Conclusions: The combination of BKM120 100 mg po q day and C 1000 mg/m2 / BID x 14 d in 21 day cycles is tolerable and appears active. PK and biomarker analysis are ongoing. A phase II trial is planned.

Acknowledgements: This study was funded by Novartis Pharmaceuticals and by a grant from Susan G. Komen for the Cure (SAC 110044).

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-16-13.

CYP2C8*3 increases risk of neuropathy in breast cancer patients treated with paclitaxel

BACKGROUND

Paclitaxel-induced neuropathy is an adverse event that often leads to therapeutic disruption and patient discomfort. We attempted to replicate a previously reported association between increased neuropathy risk and CYP2C8*3 genotype.

PATIENTS AND METHODS

Demographic, treatment, and toxicity data were collected for paclitaxel-treated breast cancer patients who were genotyped for the CYP2C8*3 K399R (rs10509681) variant. A log-rank test was used in the primary analysis of European-American patients. An additional independent replication was then attempted in a cohort of African-American patients, followed by modeling of the entire patient cohort with relevant covariates.

RESULTS

In the primary analysis of 209 European patients, there was an increased risk of paclitaxel-induced neuropathy related to CYP2C8*3 status [HR (per allele) = 1.93 (95% CI: 1.05-3.55), overall log-rank P = 0.006]. The association was replicated in direction and magnitude of effect in 107 African-American patients (P = 0.043). In the Cox model using the entire mixed-race cohort (n = 411), each CYP2C8*3 allele approximately doubled the patient's risk of grade 2+ neuropathy (P = 0.004), and non-Europeans were at higher neuropathy risk than Europeans of similar genotype (P = 0.030).

CONCLUSIONS

The increased risk of paclitaxel-induced neuropathy in patients who carry the CYP2C8*3 variant was replicated in two racially distinct patient cohorts.

Abstract PD10-07: Patients carrying CYP2C8*3 are at increased risk of paclitaxel-induced neuropathy

Background: Paclitaxel-induced neuropathy is a common, severe adverse event that seems to be related to cumulative drug exposure. Examining a neoadjuvantly treated cohort, we previously found increased neuropathy risk in patients carrying the CYP2C8*3 variant, which is associated with altered paclitaxel metabolism. To confirm this association, we examined the univariate association of CYP2C8*3 genotype and paclitaxel-induced neuropathy first in an independent cohort, then as a combined multivariable analysis.

Methods: CYP2C8*3 is more common in Caucasians (Allele Frequency [AF]=0.14) than other racial groups (African-American AF=0.04). To avoid potential issues with population stratification, initial univariate analysis was performed on 209 self-reported Caucasian breast cancer patients from a prospective cohort study (LCCC 9830) who were treated with paclitaxel-based regimens and had not been previously analyzed. The CYP2C8*3 (K399R) variant was genotyped on the Affymetrix DMET™ Plus Chip (Affymetrix, Inc., Santa Clara, CA, USA) at Gentris Corp. (Gentris Corp. Morrisville, NC) from germline DNA collected at diagnosis. The primary endpoint was the dose-at-grade 2+ neuropathy as defined by NCI CTC criteria. Statistical analysis was carried out using the log-rank test across the three genotype groups (*1/*1, *1/*3, *3/*3). The Caucasian cohort was then combined with 78 Caucasian patients from our previous neoadjuvant study and 124 non-Caucasian patients to build a multivariate Cox proportional hazards model. We performed model selection using backward elimination with AIC on a main effects model that included potential covariates: race, age, diabetes, paclitaxel schedule, and supplemental neuropathy therapy. A standard alpha=0.05 was used as the significance threshold for the primary log-rank analysis.

Results: The allele frequencies were similar to that expected and the distribution of alleles conformed to Hardy-Weinberg proportions for the Caucasian and non-Caucasian cohorts. 209 Caucasian breast cancer patients treated with paclitaxel were evaluated in the primary analysis, 35 (17%) of whom experienced grade 2+ peripheral neuropathy. The risk of neuropathy was significantly associated with CYP2C8*3 in the primary analysis (log-rank p = 0.006). A combined cohort of 411 patients were evaluable in the Cox model, 76 (18%) of whom experienced grade 2+ neuropathy during treatment. After backward elimination of covariates that did not contribute to the Cox model, increased age (HR = 1.02 [95% CI: 1.00–1.04], p = 0.102), non-Caucasian race (HR = 1.76 [1.05–2.93], p = 0.031), and CYP2C8*3 (Additive Model: HR=1.98 [1.25–3.13], p = 0.004, no model assumed: p = 0.023) were associated with increased risk of paclitaxel-induced neuropathy.

Conclusions: We have replicated in an independent population the finding that patients carrying CYP2C8*3 are at increased risk of paclitaxel-induced neuropathy, with risk approximately doubling for each *3 variant carried. After adjusting for CYP2C8 genotype we detected an increase in neuropathy risk for non-Caucasians which is consistent with a previous finding and supports the need to better understand the overall etiology of neuropathy risk.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD10-07.

Abstract P6-11-06: A phase Ib study of LCL161, an oral inhibitor of apoptosis (IAP) antagonist, in combination with weekly paclitaxel in patients with advanced solid tumors

Background: Impaired apoptosis is a common feature of cancer cells and may contribute to chemoresistance. LCL161 is an oral small molecule antagonist of Inhibitor of Apoptosis Proteins (IAPs) that sensitizes a subset of tumors from diverse lineages to treatment with cytotoxic therapies, including paclitaxel. Multiple breast cancer models are sensitive to LCL161 as a single agent and LCL161 acts synergistically with paclitaxel in these models. A phase I study established an LCL161 dose of 1800 mg once weekly as well tolerated, with strong evidence of pharmacodynamic activity at doses ≥320 mg. This ongoing phase Ib study defines the dose limiting toxicities (DLTs), maximum tolerated dose (MTD), safety, and pharmacokinetics (PK) of LCL161 in combination with weekly paclitaxel.

Methods: Patients with advanced/metastatic solid tumors were treated with paclitaxel 80 mg/m2 each week followed by escalating doses of LCL161 administered once weekly immediately following paclitaxel. PK and biomarker sampling was performed.

Results: Thirty-two patients have received LCL161 doses of 600 mg (n = 3), 1200 mg (n = 5), 1500 mg (n = 4), and 1800 mg (n = 20). The most frequent adverse events considered LCL161-related included diarrhea (n = 11; 1 Grade 3), nausea (n = 8), fatigue (n = 7; 2 Grade 3), peripheral neuropathy (n = 6; 1 Grade 3), vomiting (n = 6), decreased appetite (n = 5), alopecia (n = 4), and anemia (n = 4). The principal DLTs were neutropenia, fatigue, and neuropathy. Significant cytokine release syndrome, the DLT of single-agent LCL161, has not been observed likely due to the use of dexamethasone as a premedication. No PK interaction between LCL161 and paclitaxel was observed. RECIST partial responses have been observed in 4 patients with diverse tumor types, including breast cancer. Preliminary antitumor activity in the expansion cohort with breast cancer patients will be presented.

Discussion: LCL161 and paclitaxel combination therapy is well tolerated, with manageable toxicities and no evidence of a PK interaction that might interfere with the activity of either agent. Enrollment of additional patients with breast and ovarian cancer into an expansion cohort is ongoing, utilizing an approach to identify those more likely to respond to treatment with IAP antagonists.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-11-06.

P2-09-07: Metabolic Response by FDG-PET in Patients (pts) Receiving Trastuzumab (T) and Lapatinib (L) for HER2+ Metastatic Breast Cancer (MBC): Correlative Analysis of TBCRC 003

Background

We evaluated the safety and efficacy of L+T in pts with 0–2 prior lines of chemotherapy (CT) for HER2+ MBC. In the context of this phase II trial, we evaluated metabolic response by FDG-PET and explored the relationship between metabolic response and clinical outcomes.

Methods: Pts with measurable, HER2+ MBC were eligible. Cohort 1: No prior T, L, or CT +T for MBC, and &gt;1 yr from adjuvant T, if received. Cohort 2: 1–2 prior lines of CT for MBC, including T, or relapse within 1 yr of adjuvant T. Pts received L 1,000 mg QD + T (2 mg/kg weekly or 6 mg/kg Q3W). Staging studies were done with CT or MRI at baseline (BL) and every 2 cycles (1 cycle=4 weeks [wks]). Objective response was assessed by local investigator according to RECIST 1.0. FDG-PET/CT was performed at BL, Wk 1, and Wk 8 per NCI guidelines. Central quality assurance, review, and analysis were performed on FDG-PET studies. Up to 5 target lesions were identified on BL FDG-PET images based on hypermetabolic uptake. Percent change in the summed maximum standardized uptake value (SUVmax) of target lesions was calculated at Wk 1 or Wk 8, compared to BL. Metabolic response was assessed according to EORTC criteria for % change in SUVmax (progressive disease [PD]: ≥25% increase; partial response [PR]: ≥25% decrease; stable disease [SD]: &lt;25% change). Metabolic response at Wk 1 was compared to Wk 8 as well as to clinical outcome, including objective response, clinical benefit, and progression-free survival (PFS).

Results: 87 pts were registered to the study. Of these, one pt did not begin protocol therapy and one pt did not have MBC on further testing, and are not included. 81/85 pts had FDG-PET data at Wk 1; 75/85 had data at Wk 8. Metabolic PR at Wk 1 was observed in 28/39 (72%) pts in Cohort 1 and 20/42 (48%) pts in Cohort 2. Metabolic PR at Wk 8 was observed in 27/34 (79%) pts in Cohort 1 and 18/41 (44%) pts in Cohort 2. Wk 1 and Wk 8 metabolic responses were similar. In cohort 1, 18/28 (64%) pts who achieved Wk 1 metabolic PR had clinical benefit by RECIST. Of pts with Wk 1 metabolic SD, 2/9 (22%) had clinical benefit. In cohort 2, 9/20 (45%) pts who achieved Wk 1 metabolic PR had clinical benefit; 5/22 (23%) who achieved Week 1 metabolic SD had clinical benefit. Exploratory analysis of progression-free survival (PFS) showed that pts in Cohort 1 who achieved Wk 1 metabolic PR experienced a median PFS of 9.3 months ([mos]; 95% CI 5.6−22.3); for pts with metabolic SD, median PFS was 1.9 mos (95% CI 0.8−5.5). For pts in Cohort 2, Wk 1 metabolic PR was associated with median PFS of 5.6 mos (95% CI 3.7−7.8), whereas for pts with metabolic SD, median PFS was 3.7 mos (95% CI 1.8−5.5).

Conclusions: L+T is associated with a high rate of early and sustained metabolic response by FDG-PET. Exploratory analyses suggest that metabolic PR may be associated with clinical benefit and longer PFS.

Phase I study of the combination of everolimus (RAD001) with 5FU/LV in patients with refractory solid malignancies

512

Background: mTOR is a controller of cellular growth and other processes that is activated by several oncogenic pathways in cancer. Everolimus is an oral inhibitor of mTOR activation. The mTOR inhibitor, temsirolimus, when combined with high dose 5FU, was limited by significant mucosal toxicity. Purpose: Phase I study to determine the maximum tolerated doses (MTD) and the safety of everolimus combined with 5FU/LV in patients with refractory solid tumors.

Methods: Using a standard 3+3 design, starting doses were everolimus 15mg weekly, and q2 weekly 5FU 400mg/m2 bolus and 1800mg/m2 infusion (over 46 hours) and LV 400mg/m2. Daily dosing of everolimus was instituted during level 3 as data emerged about improved target inhibition and adverse event profile with daily dosing. Dose escalation to the maximum planned levels was achieved: everolimus 10mg daily, 5FU 400mg/m2 bolus and 2400mg/m2 infusion, and LV 400mg/m2. Dose limiting toxicities (DLT) were assessed in cycle 1 (4 weeks), defined as any grade 3/4 non-hematologic toxicity (except grade 3 skin rash, nausea and diarrhea), or complicated grade 3-4 heme toxicity. Tumors were measured every 8 weeks.

Results: From 03/2008 and 11/2009, 21 patients were treated. Median age 58 (range 35-77), male/female 13/8, PS 0/1 10/11. One DLT was seen at dose level 1 (grade 3 hypersensitivity/angioedema); two at dose level 6 (grade 3 diarrhea, grade 3 hypophosphatemia). As such, dose level 5 is the MTD. Dose reductions were required in 4 patients for mouth sores (2), nasal sores (1), and grade 3 transaminitis (1). Responses are as follows: 11 stable disease and 8 progressive disease; 2 patients were not evaluable.

Conclusions: MTD is everolimus 5mg daily, with q2 weekly 5FU 400mg/m2 bolus and 2400mg/m2 infusion and LV 400mg/m2. We are currently expanding the study to evaluate the addition of oxaliplatin and panitumumab to the 5-FU/LV and everolimus base.

[Table: see text]

[Table: see text]

Abstract P3-14-06: Pharmacokinetic (PK) Interaction Potential of Trastuzumab-DM1 (T-DM1) and Pertuzumab (P) in Pts with HER2-Positive, Locally Advanced or MBC: Results from a Phase 1b/2 Study

Introduction

T-DM1 is an antibody-drug conjugate (ADC) composed of the cytotoxic DM1 conjugated to trastuzumab and retaining its antitumor properties. P is a HER2-directed monoclonal antibody that inhibits HER2 dimerization and subsequent signaling. The combination of T-DM1 and P has demonstrated synergistic antitumor activity in HER2-positive xenograft models. T-DM1 and P are expected to undergo proteolytic degradation with no significant involvement of cytochrome P450 isoenzymes. In contrast, DM1 is metabolized mainly by CYP3A4 and to a limited extent by CYP3A5. Therefore, a key component in evaluating this combination clinically is determining whether a PK-based drug interaction potential exists when these drugs are administered together. Assessment of PK-based therapeutic protein-ADC interaction potential is novel, as antibodies have typically been combined with chemotherapy in clinical studies. Methods

This 3+3 dose escalation, open-label, phase 1b/2 study evaluated the safety, tolerability, PK, and efficacy of T-DM1 (3.0 mg/kg q3w or 3.6 mg/kg q3w [established phase 2 dose]) in combination with P (840 mg loading dose; 420 mg q3w thereafter) in pts with HER2-positive locally advanced or MBC. Because of the half-life of both agents, staggered dosing was not a practical approach to assess the PK interaction. Thus, both drugs were administered sequentially on Day 1 of each cycle. All pts receiving study treatment were evaluated for serum concentrations of T-DM1, total trastuzumab (conjugated and unconjugated to DM1), and plasma concentrations of DM1, at pre-specified time points. To avoid the interference of P with the quantification of total trastuzumab, a new assay that allows capturing trastuzumab in the presence of P was developed and validated. PK of T-DM1 and related analytes were compared with historical single agent data by population and/or noncompartmental analyses. Whether combination with P was a significant covariate of T-DM1 clearance and central volume of distribution (V1) was tested. The confidence intervals (CIs) of the ratios of clearance and V1 of combination to monotherapy were estimated. A CI containing 1 is indicative of comparable parameters. Results

PK data were available for 63 pts. Combination with P was not a significant covariate of T-DM1 clearance and V1 (P&gt;0.05 by the log likelihood ratio test). The combination to monotherapy ratios for clearance and V1 had a 95% CI of [0.90-1.04] and [0.95-1.06], respectively, indicating comparable clearance and V1 of combination and monotherapy. The average post-hoc Bayesian estimates of T-DM1 clearance and V1 in the presence of P were 0.69±0.14 L/day and 3.3±0.41 L, which were comparable with historical measures of 0.73±0.19 L/day and 3.4±0.57 L with monotherapy. The average maximal concentration of total trastuzumab in cycle 1 was 101±29 μg/ml in the 3.0 mg/kg TDM1 dose (n=3) and 98±32 μg/ml for the 3.6 mg/kg dose (n=60). The maximum DM1 level was &lt;17 ng/mL at both T-DM1 doses. The PK of total trastuzumab and DM1 were also comparable with monotherapy (data not shown).

Conclusions

This assessment suggests that P does not alter the PK of T-DM1 when these drugs are administered together.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-14-06.

Abstract PD07-10: Breast Cancer Patients Carrying the CYP2C8*3 Variant Are More Likely To Achieve Clinical Complete Response from Neoadjuvant Paclitaxel Treatment

Background: Complete response to neoadjuvant chemotherapy is a good prognostic indicator in breast cancer patients. Neoadjuvant treatment has shown comparable efficacy to adjuvant treatment while providing an opportunity to evaluate tumor response to therapy. Paclitaxel is one of the most frequently used chemotherapeutic agents in the neoadjuvant setting. Using a candidate gene approach, we hypothesized that polymorphisms in genes relevant to the metabolism and transport of paclitaxel are associated with treatment efficacy and toxicity.

Materials and Methods: Subjects included in this study were treated with paclitaxel-containing regimens in the neoadjuvant setting. Most received sequential anthracycline-and taxane-based therapy in which clinical response to each phase was collected separately. Clinical data, including patient and tumor characteristics and treatment outcomes, was collected prospectively in an observational registry. Treatment response was measured before and after each phase of treatment by clinical tumor measurement and categorized according to RECIST criteria while toxicity data was collected from physician notes. The primary endpoint of this study was achievement of clinical complete response (cCR) during taxane treatment. Secondary endpoints included clinical response rate (cRR, complete response + partial response, cPR), any grade 3 or higher toxicity, and grade 3 or higher neuropathy from paclitaxel treatment. Blood was collected at diagnosis and genotyped using pyrosequencing. The genotypes assessed were CYP1B1*3, CYP2C8*3, CYP3A4*1b, CYP3A5*3C, ABCB1 1236, ABCB1 2677, and ABCB1 3435.

Results: 112 breast cancer patients treated with neoadjuvant paclitaxel were included in this analysis. The median age was 50, 28 were African-American, tumor stage included II (42 patients), III (60 patients), and presenting stage IV (10 patients), 60 were grade 3, 57 were ER+, and 32 were HER2+, of whom 21 received trastuzumab as part of the paclitaxel regimen. Response rate was 27.7% cCR, 31.3% cPR to the paclitaxel component. CYP2C8*3 carriers (23/112, 20.5%) had higher rates of clinical complete response to neoadjuvant paclitaxel treatment (55% versus 22%; p=.006). This association remained significant after adjustment for race, tumor grade, ER status, and whether paclitaxel treatment was preceded by another phase of chemotherapy. There were trends for increased clinical response rate (cRR; p=.052) and greater risk of grade 3 or higher peripheral neuropathy (p=.072) in subjects carrying the CYP2C8*3 variant. On multivariate analysis, other paclitaxel drug-metabolizing enzyme polymorphisms did not appear related to either response or toxicity.

Discussion: CYP2C8 is the primary enzyme responsible for paclitaxel metabolism, and the *3 variant has demonstrated decreased catalytic activity toward paclitaxel in vivo, leading to increased exposure of the patient to the active parent compound. Our results demonstrate that patients carrying CYP2C8*3 are more likely to achieve clinical complete response from neoadjuvant paclitaxel treatment, but may also be at increased risk of experiencing severe peripheral neurotoxicity.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD07-10.

Effect of aprepitant (AP) on cyclophosphamide (CPA) pharmacokinetics (PK) in early breast cancer patients

588

Background: AP, a moderate inhibitor of CYP3A4, is a selective neurokinin 1 receptor antagonist recommended by the ASCO guidelines for prevention of high and some moderately emetogenic chemotherapy regimens, including doxorubicin and CPA (AC). CPA is converted to the active 4-OH metabolite primarily by CYP2B6 (48–57%) and by CYP3A4 (12–18%). CYP3A4 also converts 10% of CPA to the N-dechloroethyl metabolite (DCE), which is responsible for neurotoxicity and nephrotoxicity. Because AP is utilized concurrently with CPA, this creates the potential for drug-drug interaction between AP and CPA. The objective of this study was to evaluate the effect of AP on the PK of CPA, 4-OH, and DCE in patients receiving AC. Methods: This double-blinded, placebo controlled, two-period, crossover study included breast cancer patients receiving regimens containing CPA 600 mg/m2 IV for at least two sequential cycles. Prior to each CPA cycle, patients were randomized to receive either oral AP (125 mg on d 1 prior to chemotherapy and 80 mg on d 2 and 3) or placebo for 3 d. During both cycles, patients were also pretreated with ondansetron 24 mg PO and dex 12 mg PO on d 1 and dex 8 mg PO once on d 2 and 3. Rescue anti-emetic medications were permitted. Serial plasma samples were obtained from 0 to 24 h after administration of CPA in combination with AP or placebo in each patient. CPA, 4-OH, and DCE plasma concentrations were determined using HPLC. Area under the plasma versus conc time curve (AUC) was calculated using WinNonlin. Results: 17 patients completed 2 cycles and were evaluated for PK. Geometric mean AUC data for CPA in combination with AP and placebo are summarized in the table. Conclusions: Based on geometric mean ratios ± 90% CI, concurrent administration of AP with CPA did not result in any significant changes in the 4-OH metabolite AUC, but did result in increased parent CPA and decreased DCE drug exposure levels. Based on these results, it is unlikely that aprepitant has a clinically significant effect on the efficacy of CPA.

[Table: see text]

[Table: see text]

Preliminary results of a phase I trial of sorafenib combined with cisplatin/etoposide (CE) or carboplatin/pemetrexed (CbP) in solid tumor patients (pts)

e13521

Background: Sorafenib had demonstrated single agent activity in non-small cell and small cell lung cancer. Methods: A non-comparative, two arm phase I trial escalating sorafenib in combination with fixed doses of CE or CbP was performed. A 3-patient cohort design was utilized to determine the maximum tolerated dose (MTD) and dose limiting toxicities (DLT). Dose level 0 for all pts was a sorafenib dose of 200 mg po BID continuously. Pts on arm A received C (60 mg/m2) on day 1 and E 120 mg/m2 on days 1,2,3 every 3 weeks with escalating doses of sorafenib. On arm B, pts received treatment with Cb (AUC=6) and P 500 mg/m2 every 3 weeks with escalating doses of sorafenib. However, excessive toxicity was observed on arm B, therefore the trial was amended such that Cb dose was lowered to AUC=5 (arm C). DLT were assessed in the 1st cycle and defined as grade (gr.) 4 anemia or thrombocytopenia, gr. 4 neutropenia lasting > 7 days, gr. ≥ 3 non-hematologic toxicity (except nausea, vomiting, and alopecia) and > 2 week dose delay. Response was assessed every 2 cycles according to RECIST, and best response was recorded. Results: Between 9/2007 and 9/2008, 20 pts were treated on the trial; median age 62 (range 47–73), male/female: 12/8, PS of 0/1: 6/14, and median number of prior therapies 2 (range 1–4). The most common tumor types were NSCLC (n=8), SCLC (n=4) and head/neck (n=2). At dose level 0 arm A (200 mg BID), 2 of 4 patients experienced DLT (gr.4 thrombocytopenia, gr.3 fatigue, febrile neutropenia and gr.4 neutropenia for > 7 days, gr.3 febrile neutropenia, diarrhea, hypokalemia, hyponatremia); 2 pts have been enrolled at dose level -1 (200 mg po QD) without DLT. Two of 3 patients enrolled on arm B at dose level 0 had gr.4 thrombocytopenia. On arm C at dose level 0 (200 mg po BID), 1/6 pts experienced DLT (gr.3 hyponatremia, dehydration, hypoglycemia). Enrollment continued at dose level 1 (400 mg po BID), but 2/5 pts experienced a DLT (both gr. 3 fatigue/anorexia). Responses observed were: PR (n=3) (all arm C), and SD (n=6). Conclusions: The MTD of sorafenib in combination with carboplatin (AUC=5) and pemetrexed 500 mg every 3 weeks is 200 mg po BID. The MTD of sorafenib in combination with cisplatin/etoposide has yet to be determined and is currently accruing at dose level -1.

[Table: see text]

Comprehensive CYP2D6 genotyping in a multiracial U.S. breast cancer population

553

Background: CYP2D6 genotyping has been suggested to avoid suboptimal responses to tamoxifen (T). Most studies to date are in white patients (pts) and focus on a limited number of genetic variants. In this clinical trial, we comprehensively examined CYP2D6 allele frequencies in women of heterogenous ethnicity taking tamoxifen (T). Methods: In LCCC 0801, pts on T ≥ 4 months and not on potent CYP2D6 inhibiting medications were genotyped using the CYP450 AmpliChip for 2D6 alleles: *1-*11, *15, *17, *19, *20, *29, *35, *36, *40, *41, *1XN, *2XN, *4XN, *10XN, *17XN, *35XN and *41XN. T dose was increased in pts with any intermediate or poor metabolizing (IM or PM) alleles [but not in pts homozygous for extensive metabolizing (EM) alleles]. Serial T metabolite levels are being assessed. Here we report the allele frequency data from this study compared to previously published cohorts. Results: 108 pts participated in the study: 24 (22%) African-Americans (AA), 76 (70%) non-Hispanic whites, 4 Asians, 3 Hispanics and 1 Spanish European. Genotyping revealed 28 (26%) EM/EM, 1 EM/UM (ultra-rapid), 29 (27%) EM/IM, 22 (20%) EM/PM, 8 (7%) IM/IM, 10 (9%) IM/PM, 9 (8%) PM/PM and 1 unknown. Conclusions: Pts in this trial had a similar frequency of PM alleles to previous reports, however a high proportion of pts have IM alleles. In particular, the majority (79%) of AA pts possess at least one variant allele. Since PM and IM genotypes have been associated with reduced T metabolism, this may have implications for T efficacy and emphasizes the importance of trials examining CYP2D6 genotyping as a determinant of T use. (Supported by Laboratory Corporation of America, Roche Diagnostics, NC UCRF, NCI SPORE.)

[Table: see text]

[Table: see text]

Phase I trial of escalating doses of ABI-007 (nanoparticle albumin-bound paclitaxel) and gemcitabine in patients (pts) with thoracic malignancies

18094

Background: ABI-007, nanoparticle albumin-bound paclitaxel, has a different toxicity profile than solvent-based paclitaxel including a lower rate of severe neutropenia. This trial was designed to determine the maximum tolerated dose (MTD) of ABI-007 in combination with gemcitabine (G) in patients with thoracic malignancies. Methods: Patients were required to have a performance status of 0–1, =3 cytotoxic chemotherapy regimens, and preserved renal, hepatic, and bone marrow function. Patients received G 1,000 mg/m2 on days 1, 8 in all cohorts and ABI-007 on day 1 at doses of 260, 300, 340 mg/m2 depending on the treatment cohort every 21 days (1 cycle = 21 days). Day 8 G dose modifications were: G held for ANC < 500 x 109/L or platelets (plts) < 50,000 x 109/L, and 75% of the G dose was given if the ANC 500–999 x 109/L or plts 50,000–99,000 x 109/L. Dose limiting toxicities (DLT) were assessed after the first cycle and were defined as: grade 3 non-hematologic toxicity, febrile neutropenia, grade 4 anemia or thrombocytopenia, ANC = 500 for = 7 days, 2-week delay in initiating the second cycle, or omission of the day 8 G. Doses were escalated in cohorts of 3–6 pts. Results: Thirteen patients were consented and 12 pts were treated (median age 62.5 years (range 35–75); median number of prior treatments 2.5 (range 1–4); tumor types: 6 non-small cell lung cancer (NSCLC), 5 small cell lung cancer (SCLC), and 1 esophageal. At an ABI-007 dose of 300 mg/m2, 1 of 6 pts experienced a DLT (omission of day 8 G due to ANC < 500), and at an ABI-007 dose of 340 mg/m2 2 of 3 patients experienced a DLT (1 pt grade 3 rash and pruritus; 1 pt grade 3 fatigue and anorexia). Additional grade 3 or 4 toxicities observed over all cycles were: neutropenia (n=2), sensory neuropathy (n=1), febrile neutropenia (n=1). G was given at full dose in 38 of the 39 cycles. Eight pts were evaluable for response by RECIST: 4 partial responses (SCLC, n=2; NSCLC, n=2), 4 stable disease (NSCLC, n=3; esophageal, n=1). Conclusions: The MTD of ABI-007 is 300 mg/m2 day 1 in combination with G 1,000 mg/m2 on days 1, 8 every 21 days. This combination was well tolerated and demonstrated activity in previously treated NSCLC and SCLC patients.

No significant financial relationships to disclose.

Pharmacokinetic (PK) and phase I study of sorafenib (S) for solid tumors and hematologic malignancies in patients with hepatic or renal dysfunction (HD or RD): CALGB 60301

3538

Background: We sought to characterize the PK and determine a tolerable dose of S in patients with HD or RD. Methods: Patients with performance status 0–2 and pathologically proven solid tumors, multiple myeloma, or non-Hodgkin’s lymphoma, for whom standard therapy was exhausted, were assigned to one of 9 cohorts: [1] Bilirubin (B) =ULN and SGOT =ULN and creatinine clearance (CC) =60 ml/min; [2] B > ULN but = 1.5 x ULN and/or SGOT > ULN; [3] CC between 40 and 59 mL/min; [4] B > 1.5 x ULN to = 3 x ULN (any SGOT); [5] CC between 20 and 39 mL/min; [6] B > 3 x ULN to 10 x ULN (any SGOT); [7] CC < 20 mL/min; [8] albumin < 2.5 mg/dL (any B/ SGOT); and [9] hemodialysis. S was administered po as a 400 mg test dose on day 1 with blood sampled before and 1, 2, 3, 4, 6, 24, and 168 hrs afterwards for PK. Total S concentrations were fit to a 2-compartment model and population parameters from previous studies were utilized. On day 8, continuous daily po S started with dose escalation in groups of at least 3 evaluable patients. Dose-limiting toxicity (DLT) by day 29 was defined as: grade 4 neutrophils or platelets; B = 1.5 x baseline in HD and = 2.5 x ULN in RD; CC reduction by > 20 mL/min in RD and >10 mL/min in HD; grade = 3 nausea/vomiting/diarrhea despite optimal supportive care; or any other grade = 3 non-hematologic toxicity. Results: Between 1/05 and 12/06, 146 patients (target 150) were registered but 12 never started therapy. With the exception of cohorts 6 and 7, at least 12 patients per cohort were evaluable. The dose level in each cohort with DLT in less than one third of patients was: [1] 400 mg bid; [2] 400 mg bid; [3] 400 mg bid; [4] 200 mg bid; [5] 200 mg bid; [6] not even 200 mg every third day tolerable; [7] n/a; [8] 200 mg qd; and [9] 200 mg qd. All DLT was non-hematologic: 9 of 12 events in patients with HD were increase in B; other DLT included abdominal pain, rash, fatigue, nausea/vomiting, hand-foot syndrome, congestive heart failure, diarrhea, hemorrhage, and hypertension. PK data are available for 51 patients. Apparent S clearance was: highly variable, median 5.69 (range 1.27 - 19.98) L/hr; not related to age, body weight, or sex; and not different among cohorts. Conclusions: Apparent S clearance does not depend on cohort. We propose the above empiric starting doses by cohort.

No significant financial relationships to disclose.

Phase I clinical trial of MLN8054, a selective inhibitor of Aurora A kinase

3577

Background: MLN8054 is a small molecule inhibitor of Aurora A kinase, with > 150-fold greater potency against this enzyme than the structurally related but functionally distinct Aurora B kinase. Because of its structural similarity to benzodiazepines, MLN8054 binds to the gamma-aminobutryic acid alpha 1 benzodiazepine (GABAA a1 BZD) receptor and in preclinical studies caused benzodiazepine-like CNS effects. Methods: MLN8054 was given as capsule by mouth for 7 consecutive days, repeated every 21 days. Cohorts of 3- 6 patients (pts) were enrolled to successively increasing doses until dose-limiting toxicity was seen in = 2 pts at a given dose level. Serial blood samples were collected to estimate PK; skin biopsies were obtained before and 6 hours after the first dose to assess inhibition of Aurora A kinase in basal epithelial cells. Results: 22 pts were enrolled to evaluate single daily doses of 5, 10, 20, 30 and 40 mg/day. MLN8054 was in general rapidly absorbed, displayed dose-proportionate exposure, and had a mean elimination half-life of 35 hours. The ratio of peak to trough plasma concentrations was approximately 5. Reversible grade 2 somnolence was first seen in 3 patients treated at 20 mg/day, and 2/4 patients treated at 40 mg/day experienced reversible grade 3 somnolence. In order to reduce the sedative effects of MLN8054, 16 additional pts were enrolled to doses of 25, 35, 45 and 55 mg/day given as divided doses on a QID schedule. Two of 4 pts treated at the 55 mg/day dose experienced reversible grade 3 somnolence, establishing 45 mg/day as the maximum tolerated total daily dose on a QID schedule. No myelosuppression or mucosal toxicity was seen at any dose with either schedule. Immunohistochemical analysis of skin biopsies from pts treated with once daily dosing did not demonstrate accumulation of cells in mitosis. Three pts with metastatic colorectal cancer treated with single daily doses of MLN8054 received = 8 cycles of treatment. Conclusions: The study is now escalating divided daily dosing of MLN8054 with the co-administration of methylphenidate. Post-treatment skin biopsies are now obtained on Day 7. Duration of treatment will be extended to 14 days, since steady-state concentrations of MLN8054 require 5–7 days of dosing, and because the effects of Aurora A kinase inhibition are duration-dependent.

No significant financial relationships to disclose.

Extended follow-up of outcome measures and analysis of prognostic factors in multiple myeloma patients treated on a phase I study with bortezomib and pegylated liposomal doxorubicin

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Background: Preclinical studies of bortezomib (bort) with pegylated liposomal doxorubicin (PLD) showed enhanced anti-tumor efficacy compared with either single agent. This led to a phase I trial in patients (pts) with advanced hematologic malignancies who received bort on days 1, 4, 8 and 11 at 0.9–1.5 mg/m2, and PLD on day 4 at 30 mg/m2, every three weeks (Blood 105:3058, 2005). Significant activity was seen, with 36% of relapsed/refractory multiple myeloma (MM) pts achieving a complete or near-complete response, while 73% attained at least a partial response. It was therefore of interest to define time to progression (TTP) and overall survival (OS) with this regimen. Methods: Additional follow-up was obtained on all 22 evaluable MM pts. TTP and OS were determined from day 1 of bort/PLD, and the Kaplan-Meier method was used to calculate time-to-event estimators. The log-rank test was used to compare TTP and time to retreatment (TTR) on bort/PLD vs. the prior therapy. Cox regression was used to evaluate covariates for association with TTP and OS. Results: Median TTP with bort/PLD was 9.3 months (mos)(95% confidence interval (CI) 8.3–22.4) versus 3.8 mos (95% CI 2.3–10.0) on the pt’s prior therapy (p=0.04). Similarly, the median TTR after bort/PLD was prolonged (p=0.04) compared with TTR after the prior regimen, with 3 pts having not yet received their next therapy. With a median follow-up of 36 mos, 13 of these patients (59%) remain alive, and the median OS has not yet been reached. Karnofsky performance status was significantly associated with TTP (p=0.02), while the hematocrit (hct; p=0.06) and IgA subtype (p=0.08) had borderline significance. Hct was significantly associated with OS (p=0.03), while the number of prior regimens (p=0.07) and the platelet count (p=0.06) had borderline significance. Conclusions: Bort alone induced a median TTP of 6.6 mos and OS of 16 mos in MM (N Engl J Med 348: 2609, 2003). The current results support the possibility that the bort/PLD regimen may improve upon TTP, and especially OS, compared with bort alone. This hypothesis is being studied in a randomized, international phase 3 trial ( NCT00103506 ) comparing bort and bort/PLD.

No significant financial relationships to disclose.

Ovarian ablation as adjuvant therapy for breast cancer

For more than 100 years ovarian ablation has been used as treatment for breast cancer. There are several methods of ovarian ablation including surgical oophorectomy, radiation-induced ablation, and chronic use of luteinizing hormone-releasing hormone (LHRH) analogs. In addition, there is some suggestion that cytotoxic chemotherapy may act in part by inducing ovarian ablation in premenopausal breast cancer patients. Of the numerous case series and clinical trials of ovarian ablation performed in the past century, many have been fraught with methodologic problems. The Early Breast Cancer Trialists' Collaborative Group (EBCTCG) meta-analysis of 12 properly randomized trials shows a significant improvement in disease-free survival (DFS) and overall survival for women who underwent ovarian ablation as adjuvant therapy compared with those who did not. However, a number of questions remain. The relative efficacy of chemotherapy and ovarian ablation and the value of combining ovarian ablation with chemotherapy or other endocrine therapy have not yet been determined. This articles reviews and compares the methods of ovarian ablation, and discusses the EBCTCG overview data, as well as the newer and ongoing trials, which may answer the remaining questions about the optimal use of this therapy in the adjuvant treatment of breast cancer.

A phase I and pharmacologic evaluation of the DNA intercalator CI-958 in patients with advanced solid tumors

5-[(2-Aminoethyl)amino]-2-[2-(diethylamino)ethyl]-2H-[1]benzothiopyra no[4,3,2-cd]-indazol-8-ol trihydrochloride (CI-958) is the most active member of a new class of DNA intercalating compounds, the benzothiopyranoindazoles. Because of its broad spectrum and high degree of activity as well as a favorable toxicity profile in preclinical models, CI-958 was chosen for further development. The Phase I study described here was undertaken to determine the toxicity profile, maximum tolerated dose, and pharmacokinetics of CI-958 given as an i.v. infusion every 21 days. Adult patients with advanced refractory solid tumors who had adequate renal, hepatic, and hematological function, life expectancy, and performance status were eligible for this study. Written informed consent was obtained from all patients. Patients received a 1- or 2-h infusion of CI-958 at 21-day intervals. The starting dose was 5.2 mg/m2, and at least three patients were evaluated at each dose level before proceeding to a new dose level. A pharmacokinetically guided dose escalation design was used until reaching a predetermined target area under the plasma concentration versus time curve (AUC), after which a modified Fibonacci scheme was used. Forty-four patients (21 men and 23 women; median age, 59 years) received 162 courses of CI-958. Neutropenia and hepatorenal toxicity were the dose-limiting toxicities, which defined the maximum tolerated dose of CI-958 to be 875 mg/m2 when given as a 2-h infusion every 21 days. There were no tumor responses. Two patients had stable disease for >250 days. The recommended Phase II dose is 560 mg/m2 for patients with significant prior chemotherapy and 700 mg/m2 for patients with minimal prior chemotherapy. Pharmacokinetic analysis of plasma and urine concentration-time data from each patient was performed. At the recommended Phase II dose of 700 mg/m2, mean CI-958 clearance was 370 ml/min/m2, mean AUC was 33800 ng-h/ml, and mean terminal half-life (t1/2) was 15.5 days. The clearance was similar at all doses, and plasma CI-958 AUC increased proportionally with dose, consistent with linear pharmacokinetics. The percentage reduction in absolute neutrophil count from baseline was well predicted by AUC using a simple Emax model. The pharmacokinetically guided dose escalation saved five to six dose levels in reaching the maximum tolerated dose compared with a standard dose escalation scheme. This may represent the most successful application to date of this dose escalation technique.

A prospective pharmacologic evaluation of age-related toxicity of adjuvant chemotherapy in women with breast cancer

Despite increasing evidence of benefit from adjuvant chemotherapy, older women with breast cancer are commonly given less aggressive treatment than younger patients. Conflicting prior data regarding age-related toxicity prompted this prospective study. Forty-four women (aged 35-79 years) with early-stage breast cancer were treated with four cycles of adjuvant therapy with doxorubicin 60 mg/m2 i.v. and cyclophosphamide 600 mg/m2 i.v. every 21 days. They were monitored for myelosuppression, cardiotoxicity, and decrease in quality of life. Pharmacokinetics were analyzed using cycle 1 plasma samples. Bone marrow granulocyte and macrophage colony-forming units (CFU-GM) were assayed in vitro for dose response to 4-hydroperoxycyclophosphamide and doxorubicin before cycle 1. There was moderate evidence of age-related decrease in nadir absolute neutrophil count (ANC) when age was viewed as a continuous variable. On average there was a 10/microliter drop in cycle 1 nadir ANC for every year increase in age (p = 0.02). However, when age was viewed as a categorical variable (age < 65 vs. > or = 65 years), a similar proportion of women in each group reached an ANC < 100 (18% vs. 19%). Neither neutropenic complications, alteration in cardiac function, nor change in quality of life scores were significantly age related (p > 0.12). Pharmacokinetic analyses did not demonstrate age-related differences in the clearance of either doxorubicin or cyclophosphamide (p > 0.8). Pharmacodynamic analysis of individual patient bone marrow progenitor cell sensitivity did not reveal any correlation with age (p > 0.48). In women undergoing adjuvant therapy for breast cancer, no clinically significant age-related trends in toxicity were observed. These data suggest that older age alone should not exclude patients from receiving adjuvant therapy with doxorubicin and cyclophosphamide.

Recent advances in systemic therapy for breast cancer

During the past year there have been a number of important advances in the area of systemic therapy for breast cancer. Combined chemoendocrine therapy has been shown to be more effective than tamoxifen alone in the adjuvant therapy of node-negative estrogen receptor-positive breast cancer. Preliminary results of a randomized trial suggest that the addition of paclitaxel to adjuvant AC (Adriamycin and Cytoxan) improves survival in patients with operable node-positive disease. In the treatment of metastatic disease, preliminary results of a randomized trial have shown docetaxel to be superior to doxorubicin in response rate. In hormonal therapy, third generation aromatase inhibitors have replaced megestrol acetate as second-line hormonal therapy in receptor-positive disease. There are promising recent data about anti-HER-2 antibody therapy and other new approaches. This article reviews these and other recent advances in the systemic therapy of breast cancer.

Does information from axillary dissection change treatment in clinically node-negative patients with breast cancer? An algorithm for assessment of impact of axillary dissection

OBJECTIVE

The authors assessed the impact of axillary dissection on adjuvant systemic therapy recommendations in patients with breast cancer.

SUMMARY BACKGROUND DATA

With increasing use of systemic therapy in node-negative women and the desire to reduce treatment morbidity and cost, the need for axillary dissection in clinically node-negative patients with breast cancer has been challenged.

METHODS

Two hundred eighty-two women with clinically negative axillae were analyzed using a model treatment algorithm. Systemic therapy was assigned with and without data from axillary dissection. Treatment shifts based on axillary dissection data were scored.

RESULTS

Twenty-seven percent of clinically node-negative women had pathologically positive nodes. Eight percent of T1a and 10% of T1b tumors had positive nodes and would have been undertreated without axillary dissection. Seven percent of premenopausal women with tumors < 1 cm and 13% with tumors > or = 1 cm had treatment changed by axillary dissection. For women 50 to 60 years of age, 10% with tumors < 1 cm, 17% with tumors 1 to 2 cm with positive prognostic features, and 4% with poor prognostic features had significant treatment shifts after axillary dissection. For clinically node-negative women older than 60 years of age not eligible for chemotherapy, only 3% of those with tumors < 1 cm and none of those with tumors > or = 1 cm had their treatment changed by findings at axillary dissection. Treatment shifts based on axillary dissection were larger if the treatment algorithm allowed for more varied or more aggressive treatment options.

CONCLUSIONS

Data obtained from axillary dissection will alter adjuvant systemic therapy regimen in a significant number of clinically node-negative women younger than 60 years of age and for older women eligible to receive chemotherapy.

The product of the H19 gene may function as an RNA

The mouse H19 gene was identified as an abundant hepatic fetal-specific mRNA under the transcriptional control of a trans-acting locus termed raf. The protein this gene encoded was not apparent from an analysis of its nucleotide sequence, since the mRNA contained multiple translation termination signals in all three reading frames. As a means of assessing which of the 35 small open reading frames might be important to the function of the gene, the human H19 gene was cloned and sequenced. Comparison of the two homologs revealed no conserved open reading frame. Cellular fractionation showed that H19 RNA is cytoplasmic but not associated with the translational machinery. Instead, it is located in a particle with a sedimentation coefficient of approximately 28S. Despite the fact that it is transcribed by RNA polymerase II and is spliced and polyadenylated, we suggest that the H19 RNA is not a classical mRNA. Instead, the product of this unusual gene may be an RNA molecule.