P1-17-06: A Phase II Trial of the CDK 4/6 Inhibitor PD0332991 in Women with Advanced Breast Cancer

Background: Dysregulation of the G1/S checkpoint of the cell cycle is a feature of many breast cancers. PD0332991, a potent oral inhibitor of cyclin-dependent kinases (CDKs) 4 and 6 is well-tolerated and has demonstrated activity in a phase I trial in a variety of solid tumors at a phase II dose of 125 mg daily on a 3 week on/1 week off schedule. Preclinical data suggest that this agent is most active in ER+ (luminal) breast cancers. We are performing a phase II study of PD0332991 in women with advanced breast cancer, one of several parallel disease cohorts under study.

Methods: Patients with histologically-confirmed stage IV breast cancer were eligible if they had primary or metastatic tumor which stained positive for retinoblastoma (Rb) protein by immunohistochemistry, disease measureable by RECIST criteria and adequate organ function/performance status. Treatment was initiated with PD0332991 at 125 mg orally, days 1 - 21 of a 28-day treatment cycle. Tumor assessments occurred after every 2 cycles (8-week intervals). The primary objective was to determine the safety and response rates in cohorts of 15 patients per tumor type; 15 patients per arm provided 80% power to detect a 15% (1/15) response rate per disease that would lead to further cohort expansion. Secondary objectives include PK, PD and predictive biomarker assessment.

Results: 36 patients were screened, 32 (89%) stained positive for Rb, and 14 have enrolled on study. The only reported toxicites are neutropenia (7 patients, 4 grade 3/4), thrombocytopenia (1 patient, grade 1) and fatigue (1 patient, grade 2). 3 patients (23%) have had dose interruptions and 5 (38%) have had dose-reduction for neutropenia, though no episodes of febrile neutropenia have occurred. Among 11 patients assessable for response to date, there is 1(7%) partial response (PR), 6 (43%) with stable disease (SD) and 4 (29%) with progressive disease (PD). 3 of 6 patients with stable disease have received greater than 6 months of therapy, and these sustained responses have occurred with dosing as low as 50 mg/day. All PR/SD have occurred in patients with ER+ tumors; all PD have been in patients with triple negative (ER-/PR-/Her2-) disease. The cyclin D1 status of all patients are being assessed. Of the 10 ER+ patients, 3 are cyclin D1 amplified, 5 are non-amplified and 2 are pending assessment. 2 in 4 cyclin D1 non-amplified patients had SD, while 2 of 2 evaluable patients with amplification had SD. PK and PD analyses are in progress.

Conclusions: PD 0332991 is an extremely well-tolerated, oral CDK 4/6 inhibitor that demonstrates prolonged single-agent activity in ER+ breast cancer patients who have progressed on hormonal therapy. These data have prompted expansion of this breast cancer cohort to further delineate activity and translational studies examining predictors of response are underway.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-17-06.

Tobacco, alcohol and drug use among dental undergraduates at one English university in 1998 and 2008

OBJECTIVE

To estimate the prevalence of tobacco, alcohol and drug use among dental undergraduates at one English university in 2008, and compare these with prevalence in 1998.

DESIGN

Cross-sectional survey using an anonymous self-report questionnaire.

SUBJECTS AND METHODS

In 2008 all 384 dental undergraduates at one English university were sent a questionnaire in order to obtain data on the frequency and amount of tobacco, alcohol, cannabis and other illicit drugs used before and during their time as a dental undergraduate. The same survey had been conducted on dental undergraduates at the university 10 years earlier.

RESULTS

Tobacco smoking was reported by 27% of males and 13.5% of females, a reduction from 1998 (42% of males and 32% of females) being significant among females. 63% of males and 69.5% of females reported drinking alcohol: significantly fewer than in 1998 (82% males and 90% females). Binge drinking was reported by 69.5% of males compared to 56% in 1998. In females 66% binged compared to 58.5% in 1998. The increase in males was significant. 62% of males and 68% of females had never used cannabis compared to 38% in males and 50.5% of females in 1998, a significant reduction. A significant reduction in amphetamine use was reported among both male and female undergraduates in 2008 compared to 1998 and a significant increase in amyl nitrate use was reported by females. Reported illicit drug use was associated with alcohol drinking, and particularly with tobacco use.

CONCLUSION

Dental undergraduates at one English university in 2008 when compared to those in 1998 are reported to be significantly less likely to drink alcohol, use cannabis and amphetamines. If female, they are significantly less likely to smoke tobacco and overestimate the number of units of alcohol they can safely consume in a week, but more likely to use amyl nitrate. If male, those who drink alcohol are significantly less likely to drink at a level of increased risk, but more likely to binge drink.

Jamaican youth health status 2005

The purpose of this survey is to determine health-seeking behaviour, nutritional status and lifestyles of adolescents aged 10-15 years. A random sample of 3003 (1422 males and 1581 females) schoolchildren, aged 10-15 years, was studied in a cross-sectional, interviewer-administered school-based survey conducted in all school types islandwide in a nationally representative sample of Jamaican children currently attending school. Some 3003 youths, 1422 males and 1581 females were interviewed. Males and females had similar healthcare-seeking behaviour but fewer students attending schools in rural areas reported having their eyes or hearing checked, or had seen a dentist than those attending urban schools. Some twelve per cent of adolescents were overweight/obese. More females than males and more urban than rural students were overweight or obese. More boys (86.3%) were physically active in the last week than girls (75%). Physical activity peaked at age 13 years and was lowest at ages 11 and 14-15 years. Some 13% of adolescents 10-15 years old reported having had sexual intercourse, with boys being four times as likely as girls to report sexual activity (OR - 4.97; C.I. - 3.82, 6.47). The median age of sexual debut was 15.43 years for boys and over 15 years for girls. One-third of adolescents drank alcohol and 3% smoked marijuana in the past year. More boys than girls used drugs (p < 0.01). Some 14% of adolescents felt lonely, sad or wanted to cry most of the time/always. One-tenth seriously considered suicide. This study concluded that most adolescents attending primary and secondary schools in Jamaica were not involved in risky behaviour. However, it reveals some critical areas of concern with regard to nutritional status and physical activity, emotional well-being, drug use and sexual activity.

Cardiac safety of docetaxel/cyclophosphamide/trastuzumab (DCH) as adjuvant therapy for HER-2 (+) early stage breast cancer

e11577

Background: The addition of trastuzumab to adjuvant chemotherapy is standard for Her2(+) breast cancer. In our practice, adjuvant docetaxel/cyclophosphamide (DC) + 1 yr of trastuzumab is offered to pts with low-risk Her2(+) disease. Although the HERA trial allowed the use of a variety of chemotherapy regimens to combine with trastuzumab, it predates the acceptance of DC as an adjuvant care-standard and therefore the safety profile of DCH has not been reported. Methods: We conducted a two-center, retrospective cohort study including all pts treated with adjuvant DCH between 12/06 and 3/08 to assess its safety profile. Using the CTCAE criteria, records were screened for toxicity from DCH initiation to the present. The primary outcome was cardiac toxicity defined as clinical CHF or a confirmed significant LVEF decline (≥ 16% decrease in EF from baseline or EF < 50% + ≥ 10% decrease from baseline). Results: 27 pts, mean age 54, were identified with a median follow-up of 23.4 months (range 12.2- 42.0 months). The mean tumor size was 1.4 cm (0.5–4.3 cm) with 84% hormone receptor(+), 96% node(-) and 100% Her2(+) by FISH or IHC. 52% of pts received DCH concurrently and 48% received trastuzumab following DC. Baseline mean EF was 65% (53–86%). EF assessments were performed every 3 months/pt. 7.4% and 11.1% of pts had a prior history of anthracycline exposure or cardiac disease respectively. 11.1% of pts experienced a significant LVEF decline occurring on ≥ 2 sequential EF measurements. The trastuzumab discontinuation rate was 3.7% (1 pt). No pt developed clinical CHF. 88% of pts have now completed trastuzumab therapy. 33% of pts received pegfilgrastim with chemotherapy. 25% of pts experienced grade III-IV neutropenia. Grade III-IV anemia and thrombocytopenia were not observed. Trastuzumab-related infusion reactions were observed in 1 pt and did not warrant drug discontinuation. At this time all pts are alive and no patient has experienced disease recurrence. Conclusions: The DCH regimen, given in sequence or concomitantly, appears to be a safe and effective adjuvant treatment for women with Her2(+) disease. Along with docetaxel/carboplatin/trastuzumab, DCH represents another acceptable non-anthracycline containing regimen for low-risk, Her2(+) pts.

No significant financial relationships to disclose.

Prevalence of hepatitis B, tetanus, hepatitis A, human immunodeficiency virus and feasibility of vaccine delivery among injecting drug users in Bangkok, Thailand, 2003-2005

OBJECTIVES

To estimate the prevalence of hepatitis B virus (HBV), tetanus, hepatitis A virus (HAV) and human immunodeficiency virus (HIV) in injecting drug users (IDUs), risk factors associated with infection and the feasibility of HBV vaccine delivery in HBV seronegatives.

METHODS

Cross-sectional seroprevalence survey of 1535 IDUs recruited from 17 Bangkok Metropolitan Administration (BMA) methadone clinics and HBV vaccination of seronegatives.

RESULTS

Prevalence of antibody to HBV, tetanus, HAV and HIV was 87.8%, 68.1%, 60.2% and 35.9%, respectively. Prevalence of HBV and HAV increased with increasing age; prevalence of tetanus decreased with increasing age. Being HIV seropositive was related inversely to income and being tetanus seronegative. Of the 189 HBV seronegative IDUs, 81.0% completed the vaccine series. IDUs with HIV had a 6.5-fold odds of vaccine non-response.

CONCLUSIONS

These data underscore the need for, and feasibility of, vaccine delivery in this population and support targeting efforts at high-risk age groups.