Neoadjuvant cetuximab, twice-weekly gemcitabine, and intensity-modulated radiotherapy (IMRT) in patients with pancreatic adenocarcinoma.

BACKGROUND: Neoadjuvant therapy has been investigated for localized and locally advanced pancreatic ductal adenocarcinoma (PDAC) but no standard of care exists. Combination cetuximab/gemcitabine/radiotherapy demonstrates encouraging preclinical activity in PDAC. We investigated cetuximab with twice-weekly gemcitabine and intensity-modulated radiotherapy (IMRT) as neoadjuvant therapy in patients with localized or locally advanced PDAC. EXPERIMENTAL DESIGN: Treatment consisted of cetuximab load at 400 mg/m(2) followed by cetuximab 250 mg/m(2) weekly and gemcitabine 50 mg/m(2) twice-weekly given concurrently with IMRT to 54 Gy. Following therapy, patients were considered for resection. RESULTS: Thirty-seven patients were enrolled with 33 assessable for response. Ten patients (30%) manifested partial response and 20 (61%) manifested stable disease by RECIST. Twenty-five patients (76%) underwent resection, including 18/23 previously borderline and 3/6 previously unresectable tumors. Twenty-three (92%) of these had negative surgical margins. Pathology revealed that 24% of resected tumors had grade III/IV tumor kill, including two pathological complete responses (8%). Median survival was 24.3 months in resected patients. Outcome did not vary by epidermal growth factor receptor status. CONCLUSIONS: Neoadjuvant therapy with cetuximab/gemcitabine/IMRT is tolerable and active in PDAC. Margin-negative resection rates are high and some locally advanced tumors can be downstaged to allow for complete resection with encouraging survival. Pathological complete responses can occur. This combination warrants further investigation.

Phase I clinical and pharmacokinetic study of perillyl alcohol administered four times a day.

We conducted a phase I dose-escalation trial of perillyl alcohol (POH; NSC 641066) given p.o. on a continuous four times a day basis to characterize the maximum tolerated dose, toxicities, pharmacokinetic profile, and antitumor activity. Sixteen evaluable patients with advanced refractory malignancies were treated at the following doses: level 1 (L1), 800 mg/m2/dose; L2, 1200 mg/m2/dose; L3, 1600 mg/m2/dose. POH was formulated in soft gelatin capsules containing 250 mg of POH and 250 mg of soybean oil. The predominant toxicities seen were gastrointestinal (nausea, vomiting, satiety, and eructation), which were dose limiting. There appeared to be a dose-dependent increase in levels of the two main metabolites, perillic acid and dihydroperillic acid. No significant differences were seen whether the drug was taken with or without food. There was a trend toward decreasing metabolite levels on day 29 compared with days 1 and 2. Peak metabolite levels were seen 1-3 h post ingestion. Metabolite half-lives were approximately 2 h. Approximately 9% of the total dose was recovered in the urine in the first 24 h, the majority as perillic acid. Evidence of antitumor activity was seen in a patient with metastatic colorectal cancer who has an ongoing near-complete response of > 2 years duration. Several other patients were on study for > or = 6 months with stable disease. The maximum tolerated dose of POH given continuously four times a day was 1200 mg/m2/dose. Gastrointestinal toxicity was dose limiting, although significant interpatient variability in drug tolerance was seen.

Pilot and safety trial of carboplatin, paclitaxel, and thalidomide in advanced non small-cell lung cancer.

We performed a pilot study to assess the safety of thalidomide in combination with standard chemo-therapy in patients with advanced non small-cell lung cancer. Patients with unresectable stage IIIA, IIIB, or IV disease were enrolled starting in July 1999. Patients received paclitaxel 225 mg/m2 over 3 hours and carboplatin area under the curve = 6.0 with thalidomide at a starting daily dose of 200 mg. The thalidomide dose was escalated, if tolerated, by 200 mg per week to a target dose of 1000 mg per day and could continue for up to 6 months. Patients with stages IIIA and IIIB disease without effusion received radiotherapy with concurrent thalidomide after 2 cycles of chemotherapy. Nine patients were enrolled: one with IIIA disease, three with IIIB disease, and five with stage IV disease. Five of nine patients had previously been treated with chemotherapy and/or radiotherapy. The most frequent side effects noted were fatigue, myalgia, constipation, neuropathy, and myelosuppression. Sixteen of the 17 (94%) episodes of grade 3 or 4 hematologic toxicity occurred in the five patients who had previously received chemotherapy, although no patients developed neutropenic fever. The median tolerated daily thalidomide dose was 600 mg. One patient with IIIA disease had a partial response after 2 cycles of chemotherapy and went on to receive radiotherapy with thalidomide. One patient with stage IV disease continues on this study with stable disease at 187 days. The median time to progression was 118 days. This preliminary data supports the further investigation of this combination in chemotherapy-naive patients with advanced non small-cell lung cancer.

Drug development in prostate cancer.

Despite strategies aimed at early detection and treatment, prostate cancer remains a leading cause of morbidity and mortality among males. Current therapies have limited impact on the natural history of metastatic hormone-refractory prostate cancer (HRPC). With an improved understanding of tumor biology, including apoptosis, differentiation, cell cycling and signaling, and angiogenesis, many potential new targets for therapy have been unveiled. Modulation of these processes may result in cytotoxic or cytostatic effects. The evaluation of therapies based on manipulation of these targets may not be adequately addressed by current study designs and traditional parameters of efficacy. Examples of agents currently in clinical trials that illustrate some of the challenges presented to clinical investigators include monoterpenes such as perillyl alcohol (POH), vitamin D analogs, flavones such as flavopiridol, and angiogenesis inhibitors. Agents such as these are aimed at unique cellular targets and will require novel approaches to determine their clinical utility. Unfortunately, in the United States, only a small proportion of cancer patients, including prostate cancer patients, are enrolled in clinical trials. We must do better to efficiently assess promising new treatment approaches and improve outcome for our patients.

Phase I clinical trial of perillyl alcohol administered daily.

Perillyl alcohol (POH; NSC-641066), a naturally occurring monoterpene, has shown antitumor and preventive activity in preclinical studies in rodent models. Drug-related activities that have been observed include the induction of apoptosis, cell cycle arrest, the inhibition of posttranslational modification of proteins that are involved in signal transduction, and differential gene regulation. We treated 18 patients who had advanced malignancies with POH, which was given on a continuous three-times-a-day schedule at the following doses: (a) level 1 (L1), 800 mg/m2/dose; (b) level 2 (L2), 1600 mg/m2/dose; and (c) level 3 (L3), 2400 mg/m2/dose. The main toxicity, which seemed to be dose related, was gastrointestinal and included nausea and vomiting, anorexia, unpleasant taste, satiety, and eructation. Two heavily pretreated ovarian cancer patients experienced reversible > or =grade 3 granulocytopenia. Grade 1-2 fatigue was also noted. The parent drug was not detectable in the plasma. The mean peak plasma levels of the two main metabolites on days 1 and 29 were 175 and 139 microM (L1), 472 and 311 microM (L2), and 456 and 257 microM (L3) for perillic acid (PA) and 7.1 and 9.8 microM (L1), 34.2 and 34.0 microM (L2), and 26.2 and 23.4 microM (L3) for dihydroperillic acid (DHPA). Peak levels were noted 2-3 h postingestion for PA and 3-5 h postingestion for DHPA. Metabolite half-lives measured about 2 h for each. POH, PA, and DHPA were detectable in the urine of all patients at L3. About 9% of the total dose was recovered in the first 24 h. The majority was recovered as PA; less than 1% was recovered as POH. Disease stabilization for > or =6 months was seen, although no objective tumor responses were noted. Further study of POH continues with a more frequent dosing schedule.