Marjorie Perloff

Phase I Dose Escalation Pharmacokinetic Study in Healthy Volunteers of Resveratrol, a Potential Cancer Chemopreventive Agent

The red grape constituent resveratrol possesses cancer chemopreventive properties in rodents. The hypothesis was tested that, in healthy humans, p.o. administration of resveratrol is safe and results in measurable plasma levels of resveratrol. A phase I study of oral resveratrol (single doses of 0.5, 1, 2.5, or 5 g) was conducted in 10 healthy volunteers per dose level. Resveratrol and its metabolites were identified in plasma and urine by high-performance liquid chromatography-tandem mass spectrometry and quantitated by high-performance liquid chromatography-UV. Consumption of resveratrol did not cause serious adverse events. Resveratrol and six metabolites were recovered from plasma and urine. Peak plasma levels of resveratrol at the highest dose were 539 ± 384 ng/mL (2.4 μmol/L, mean ± SD; n = 10), which occurred 1.5 h post-dose. Peak levels of two monoglucuronides and resveratrol-3-sulfate were 3- to 8-fold higher. The area under the plasma concentration curve (AUC) values for resveratrol-3-sulfate and resveratrol monoglucuronides were up to 23 times greater than those of resveratrol. Urinary excretion of resveratrol and its metabolites was rapid, with 77% of all urinary agent-derived species excreted within 4 h after the lowest dose. Cancer chemopreventive effects of resveratrol in cells in vitro require levels of at least 5 μmol/L. The results presented here intimate that consumption of high-dose resveratrol might be insufficient to elicit systemic levels commensurate with cancer chemopreventive efficacy. However, the high systemic levels of resveratrol conjugate metabolites suggest that their cancer chemopreventive properties warrant investigation. (Cancer Epidemiol Biomarkers Prev 2007;16(6):1246–52)

Combination chemotherapy with mastectomy or radiotherapy for stage III breast carcinoma: a Cancer and Leukemia Group B study.

One hundred thirteen evaluable patients with previously untreated stage III breast carcinoma were treated with three monthly cycles of cyclophosphamide (CYC), doxorubicin (DOX), 5-fluorouracil (5-FU), vincristine (VCR), and prednisone (PRED) (CAFVP). Subsequently, 91 (81%) were deemed operable. Patients were then randomized to receive surgery or radiotherapy (RT) to determine which of these modalities afforded better local tumor control. All patients also received 2 additional years of CAFVP in a further attempt to eradicate local disease and systemic micrometastases. Forty-one of the randomized patients have relapsed. Approximately half of the initial relapses in each arm were local. The overall duration of disease control was similar following either modality, with a median of 29.2 months for surgery patients and 24.4 months for RT patients. Similarly, there was no major difference in survival related to randomized treatment with an overall median of 39 months (median follow-up 37 months). Pre- or perimenopausal status and inflammatory disease were associated with shorter disease control and survival. Treatment was generally well tolerated and toxicity was acceptable. This study demonstrates that prolonged control of stage III breast carcinoma can be achieved with combined modality therapy in which cytotoxic chemotherapy precedes and follows treatment directly primarily at the breast tumor, using either surgery or RT. Nevertheless, new regimens must be designed if significant advances that may lead to the cure of this disease are to be achieved.

Resveratrol modulates drug- and carcinogen-metabolizing enzymes in a healthy volunteer study.

Resveratrol has been shown to exhibit cancer-preventive activities in preclinical studies. We conducted a clinical study to determine the effect of pharmacologic doses of resveratrol on drug- and carcinogen-metabolizing enzymes. Forty-two healthy volunteers underwent baseline assessment of cytochrome P450 (CYP) and phase II detoxification enzymes. CYP1A2, CYP2D6, CYP2C9, and CYP3A4 enzyme activities were measured by the metabolism of caffeine, dextromethorphan, losartan, and buspirone, respectively. Blood lymphocyte glutathione S-transferase (GST) activity and GST-π level and serum total and direct bilirubin, a surrogate for UDP-glucuronosyl transferase (UGT) 1A1 activity, were measured to assess phase II enzymes. After the baseline evaluation, study participants took 1 g of resveratrol once daily for 4 weeks. Enzyme assessment was repeated upon intervention completion. Resveratrol intervention was found to inhibit the phenotypic indices of CYP3A4, CYP2D6, and CYP2C9 and to induce the phenotypic index of 1A2. Overall, GST and UGT1A1 activities were minimally affected by the intervention, although an induction of GST-π level and UGT1A1 activity was observed in individuals with low baseline enzyme level/activity. We conclude that resveratrol can modulate enzyme systems involved in carcinogen activation and detoxification, which may be one mechanism by which resveratrol inhibits carcinogenesis. However, pharmacologic doses of resveratrol could potentially lead to increased adverse drug reactions or altered drug efficacy due to inhibition or induction of certain CYPs. Further clinical development of resveratrol for cancer prevention should consider evaluation of lower doses of resveratrol to minimize adverse metabolic drug interactions. Cancer Prev Res; 3(9); 1168–75. ©2010 AACR.

Tolerability of the synthetic retinoid fenretinide® (HPR)☆

Fenretinide, N-(4-hydroxyphenyl)retinamide (HPR), is a synthetic retinoid which has been proven effective in inducing cell differentiation and in inhibiting carcinogen induced mammary tumors in rodents. Because of its efficacy and low toxicity in animals, HPR has been proposed for chemopreventive evaluation in humans. Thus, a randomized trial has been conducted to select a dose which can be administered over a lengthy period of time and with acceptable toxicity. The retinoid was administered orally to patients already operated on for breast cancer in daily doses of 100, 200 and 300 mg for 6 months and subsequently at 200 mg for another 6 months. No acute toxicity was found. Dermatological toxicity was minimal and no liver function abnormalities were observed. Nausea and headaches were infrequent and always mild. Menstrual irregularities were recorded with similar frequency in the treatment and placebo groups and appeared to be more age related than drug dependent. After 6 months of treatment one of 25 patients taking 300 mg HPR daily experienced impaired night vision, confirmed by the electroretinogram, and resolved by interruption of treatment. Because the 300 mg daily dose is possibly associated with impaired dark adaptation, the recommended dose for chemoprevention trials of HPR is 200 mg per day.

Long-term tolerability of fenretinide (4-HPR) in breast cancer patients

A group of 53 patients initially participating in a phase I trial with the synthetic retinoid fenretinide was assessed for the long-term tolerability of this compound. The patients were evaluated after 42 months of drug intake at a dose of 200 mg/day, including a 3-day drug interruption at the end of each month, by the following examinations: a dermatological visit; an ophthalmological evaluation including an ophthalmological questionnaire and an electroretinogram (ERG); a study on blood chemistry and plasma retinol levels; a study on bone densities and on skeletal X-rays; and finally a psychological evaluation including various tests for anxiety, depression and overall mood. The results show that prolonged administration of fenretinide is well tolerated. No acute nor severe toxicity was observed and thus this compound can be considered a good candidate for chemoprevention trials in a variety of patient populations.

Chemotherapy versus chemoimmunotherapy (CAF v CAFVP v CMF each +/- MER) for metastatic carcinoma of the breast: a CALGB study. Cancer and Leukemia Group B.

Three combination chemotherapy regimens each with or without the methanol-extracted residue of bacillus Calmette-Guérin (BCG) (MER) were compared for efficacy. After stratification for disease-free interval and dominant sites of disease, patients were randomized to either CMF (cyclophosphamide [CYC], 100 mg/m2 orally, days 1 through 14; methotrexate [MTX], 40 mg intravenously [IV], days 1 and 8; 5-fluorouracil [5-FU], 500 mg/m2 IV, days 1 and 8), or CAF (CYC, 100 mg/m2 orally, days 1 through 14; doxorubicin [DOX], 25 mg/m2 IV, days 1 and 8; 5-FU, 500 mg/m2 IV, days 1 and 8), or CAFVP (CAF as above plus vincristine [VCR], 1.0 mg/m2 IV, days 1 and 8; and prednisone [PRED], 40 mg/m2 orally, days 1 through 14). Nonspecific immunotherapy with MER was administered in five sites at 100 micrograms or at the lowest tenfold dilution that produced a 1-cm indurated lesion. A total of 432 patients were entered, but 37 were disqualified, leaving 395 evaluable for treatment results and toxicities. One hundred thirty-five evaluable patients were randomized to chemoimmunotherapy until October 28, 1978. One hundred twenty-six evaluable patients were randomized to chemotherapy alone in the same time period. For the entire study, a total of 260 evaluable patients were randomized to chemotherapy. Chemoimmunotherapy patients were compared with the initial 126 chemotherapy patients. Chemotherapy regimens were compared among all 260 patients. Patient characteristics were similar between regimens and between chemotherapy and chemoimmunotherapy treatment groups. For patients on chemotherapy plus MER, there was no significant differences between the regimens for response frequencies: 43%, 41%, and 32%, respectively for CMF, CAF, and CAFVP. The comparable chemotherapy alone group had 36%, 58%, and 63% response, respectively. The response rates, adjusted for chemotherapy regimen, were 52% and 38% (P = .02) for chemotherapy and chemoimmunotherapy, respectively. MER was associated with painful ulcers and fevers. Thus, MER produced toxicity without response or survival benefit and further randomization after October 28, 1978 was to chemotherapy alone. For 260 evaluable patients on chemotherapy alone, the complete (CR) and partial responses (PR) were 37%, 55%, and 58%, respectively for CMF, CAF, and CAFVP. These response rates for CAF and CAFVP were significantly better than CMF (P = .01 and P less than .01, respectively). These comparisons were consistent within subgroupings such as dominant sites of disease.(ABSTRACT TRUNCATED AT 400 WORDS)

A comparison of intermittent vs. continuous and of adriamycin vs. methotrexate 5-drug chemotherapy for advanced breast cancer A Cancer and Leukemia Group B study

THE THERAPEUTIC EFFECTIVENESS OF INTERMITTENT vs. continuous combination chemotherapy and of the substitution of adriamycin for methotrexate in a 5-drug regimen was evaluated in women with metastatic breast carcinoma. Patients were randomly allocated to receive continuous therapy with cyclophosphamide, methotrexate, 5-fluo-rouracil, vincristine, prednisone (CMFVP-C, 86 patients), intermittent CMFVP (CMFVP-I, 109 patients), or intermittent CAFVP (107 patients). The CR + PR rate with CAFVP (71%) was superior to CMFVP-C (50%, p = 0.003) and to CMFVP-I (50%, p = 0.002). The remission duration with CAFVP (14 months, median) was superior to CMFVP-I (7 months) (p < 0.01), and tended to be superior to CMFVP-C (9 months) (p = 0.07). There was a survival advantage of CAFVP (19 months, median) over CMFVP-I (13 months) (p = 0.01), but not over CMFVP-C (16 months) (p = 0.24). Among CR + PR patients, the survival with CAFVP (29 months, median) was superior (p = 0.02) to both CMFVP-I (18 months) and CMFVP-C (21 months). The CMFVP-C regimen was associated with the highest incidence of leukopenia and neurologic toxicity, but the lowest incidence of GI toxicity. The results indicate that the CAFVP regimen is well tolerated and is superior to the CMFVP regimens.

A randomized trial of five and three drug chemotherapy and chemoimmunotherapy in women with operable node positive breast cancer.

Women with breast carcinoma and four or more involved ipsilateral axillary lymph nodes were randomly assigned to receive an induction course and 2 yr of maintenance chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil (CMF, 150 patients), CMF plus vincristine and prednisone (CMFVP, 166 patients), or chemoimmunotherapy with CMF plus the methanol extraction residue of BCG (CMF-MER, 85 patients). After 5 yr of accrual and a median follow-up of 34 mo, CMFVP is superior to CMF (p less than 0.01) with disease-free survival estimates at 4 yr of 60% for CMFVP compared to 45% for CMF. The disease-free survival advantage of CMFVP over CMF was greater in postmenopausal (p = 0.02) than in premenopausal patients (p = 0.09). CMF-MER was similar to CMF alone. CMF related side effects were similar in each regimen (see text), except for a greater incidence of leukopenia during induction with CMF than with CMFVP (p less than 0.01).

Fenretinide: a prototype cancer prevention drug.

Fenretinide (N-4-hydroxyphenylretinamide [4-HPR]) is a synthetic retinoid that has been examined in in vitro assays, preclinical animal models and clinical trials as a cancer chemopreventive agent. Its pharmacology, toxicity and mechanisms of action initially suggested an increased therapeutic index relative to native retinoids for the control of tumours of the breast, prostate, bladder, colon, cervix and head and neck. Although fenretinide at the doses and schedules used in several pivotal Phase II and III clinical trials has not been proven to be efficacious in reducing the incidence of cancer or in retarding the development of preneoplastic lesions, encouraging observations regarding unanticipated preventative activity, such as for ovarian cancer control, have arisen from these studies. Research in cancer therapy and the elucidation of molecular pathways activated by fenretinide have also yielded clues about how this agent might be better used in a prevention setting. Current trials are underway to re-examine both dose and schedule of fenretinide administration as well as the target tissues of interest. Investigations of potential synergism between fenretinide and other candidate chemopreventative molecules with complementary mechanisms of action may support future assessments of this prototype cancer prevention drug or its newer analogues.

Safety and Efficacy of Weekly Oral Oltipraz in Chronic Smokers

Cigarette smoking is thought to contribute to carcinogenesis by formation of DNA adducts of tobacco smoke constituents leading to genotoxic damage. The dithiolethione, oltipraz, is a putative cancer chemopreventive agent that induces phase II detoxifying enzymes in preclinical models and reduces aflatoxin adducts in humans living in areas with high dietary levels. To determine if oltipraz could reduce adduct levels of tobacco smoke constituents in the lungs and other target organs, chronic smokers were enrolled to one of three arms: 400 or 200 mg/wk oral oltipraz or placebo. Endobronchial tissue and bronchoalveolar lavage were done before and after 12 weeks of drug treatment; peripheral blood, urine, and oral saline rinse were also collected. Toxicity was assessed every 4 weeks. Fifty-nine of the 77 enrolled subjects completed the study. Of those receiving oltipraz, 15% experienced grade 2/3 toxicity, which was predominantly gastrointestinal. All subject withdrawals occurred in the oltipraz groups. There was no significant difference between pre- and post-polycyclic aromatic hydrocarbon-DNA adduct levels in lung epithelial cells measured by immunoperoxidase staining between treatment and placebo groups. Likewise, no significant differences were found in polycyclic aromatic hydrocarbon or benzo(a)pyrene-7,8-diol-9,10-epoxide adducts measured in blood, oral lining cells, or bladder lining cells. There was also no increase in mRNA or enzymatic activity of phase II enzymes and no change in glutathione levels. Thus, despite moderate drug-related toxicity, there was no significant effect on pharmacodynamic or surrogate risk biomarkers. Other agents with lower toxicity and greater activity to induce phase II enzymes are needed to definitively test the detoxification-induction paradigm in smokers.