A phase I study of sirolimus and bevacizumab in patients with advanced malignancies

Background

We performed a single institution, phase I study of sirolimus and bevacizumab, in order to determine the dose limiting toxicity (DLT) and recommended phase II doses.

Patients and methods

Eligible patients had previously treated advanced malignancies and were enrolled in three cohorts. Sirolimus 90 mg PO weekly (45 mg on days 1 and 2) was combined with bevacizumab 7.5 mg/kg (cohort #1) or bevacizumab 15 mg/kg (cohort #2) IV q3weeks. Sirolimus 4 mg PO daily was combined with bevacizumab 15 mg/kg IV q3weeks (cohort #3).

Results

Twenty-eight patients enrolled. The most common tumour types were colorectal (21%), head/neck (14%), and renal cell (11%). No DLTs were observed in cohorts #1 (4 patients) and #2 (12 patients), while two DLTs (grade 3 confusion and grade 3 fatigue) were observed in the first six patients in cohort #3 (12 patients). The most common grade 3 toxicities were fatigue (18%), hypertension (14%) and anorexia (11%). There were no responses, but one patient has had stable disease for 78 weeks.

Conclusions

The combination of sirolimus and bevacizumab at full doses is tolerable in the majority of patients. The availability and cost of sirolimus compared with other mTOR inhibitors make this an attractive agent to combine with bevacizumab.     

A phase I/II study of lenalidomide in combination with sunitinib in patients with advanced or metastatic renal cell carcinoma

BackgroundThis phase I/II study was conducted to determine the maximum tolerated dose (MTD), safety, and efficacy of lenalidomide plus sunitinib in metastatic renal cell carcinoma (RCC) patients.Patients and methodsPatients with histologically confirmed, metastatic RCC were treated with 10 mg/day lenalidomide plus 37.5 mg/day sunitinib, orally in 21-day cycles. Doses were escalated to determine the MTD in phase I, with additional patients planned at this dose in phase II. Primary end points were MTD and response rate.ResultsSixteen patients received a median of 2, 3, and 5 cycles in cohort 1 [lenalidomide 10 mg (days 1–21) and sunitinib 37.5 mg (days 1–21)], cohort 2 [lenalidomide 10 mg (days 1–21) and sunitinib 37.5 mg (days 1–14)], and cohort 3 [lenalidomide 15 mg (days 1–21) and sunitinib 37.5 mg (days 1–14)], respectively. Median treatment durations were 41, 63, and 97 days for lenalidomide; and 41, 57, and 97.5 days for sunitinib. The MTD was found to be continuous dosing of lenalidomide 10 mg/day plus sunitinib 37.5 mg/day for 14 of 21 days. Dose-limiting toxicities included neutropenia, leukopenia, thrombocytopenia, asthenia, atrial fibrillation, and increased transaminases. The most frequent grade 3–4 treatment-emergent adverse events were hematologic, including neutropenia and leukopenia. One patient achieved partial response, and seven had stable disease of which three were confirmed at subsequent tumor assessments. B cells and several T-cell subsets were modulated versus baseline.ConclusionThe dose schedules of lenalidomide and sunitinib evaluated in this study were not well tolerated; cumulative toxicity precluded enrollment at the MTD.     

Feasibility of sequential use of sunitinib and temsirolimus in advanced renal cell carcinoma

Targeted agents sunitinib and temsirolimus are effective in advanced renal cell carcinoma. Treatment algorithms for single-agent use have been proposed in order to optimize timing and type of therapy. The aim of this study was to investigate the tolerability and adverse event profile of patients who received sunitinib and temsirolimus in sequence. We performed a retrospective analysis of patients with advanced renal cell carcinoma who received temsirolimus after disease progression under sunitinib therapy. Dosages of both drugs were in accordance with the recommendations given by the respective manufacturers. Temsirolimus was provided before its official approval within a compassionate use program. Adverse event assessment followed the National Cancer Institute Common Toxicity Criteria. Thirteen patients receiving temsirolimus after progression under sunitinib were identified. Overall treatment time with targeted drugs (sunitinib/temsirolimus) was 34.8 (17–78) weeks, treatment with sunitinib was 28.6 (12–72), and with temsirolimus 6.2 (2–16) weeks, respectively, whereas mean therapy interruption time between both approaches was 4.4 (2–12) weeks. Under sunitinib, we observed 52 transient adverse events, 49 (94.2%) were of grade I/II, whereas 3 (5.8%) were of grade III. Under temsirolimus 36 adverse events, only grade I/II in nature were remarked. Sequential use of temsirolimus after progression under sunitinib seems to be feasible and results in a predictable, medically manageable side effect profile. Further evaluation is necessary to define the oncological validity of this sequencing approach.     

A randomized phase II trial of CRLX101 in combination with bevacizumab versus standard of care in patients with advanced renal cell carcinoma

BackgroundNanoparticle-drug conjugates enhance drug delivery to tumors. Gradual payload release inside cancer cells augments antitumor activity while reducing toxicity. CRLX101 is a novel nanoparticle–drug conjugate containing camptothecin, a potent inhibitor of topoisomerase I and the hypoxia-inducible factors 1α and 2α. In a phase Ib/2 trial, CRLX101 + bevacizumab was well tolerated with encouraging activity in metastatic renal cell carcinoma (mRCC). We conducted a randomized phase II trial comparing CRLX101 + bevacizumab versus standard of care (SOC) in refractory mRCC.Patients and methodsPatients with mRCC and 2–3 prior lines of therapy were randomized 1:1 to CRLX101 + bevacizumab versus SOC, defined as investigator’s choice of any approved regimen not previously received. The primary end point was progression-free survival (PFS) by blinded independent radiological review in patients with clear cell mRCC. Secondary end points included overall survival, objective response rate and safety.ResultsIn total, 111 patients were randomized and received ≥1 dose of drug (CRLX101 + bevacizumab, 55; SOC, 56). Within the SOC arm, patients received single-agent bevacizumab (19), axitinib (18), everolimus (7), pazopanib (4), sorafenib (4), sunitinib (2), or temsirolimus (2). In the clear cell population, the median PFS on the CRLX101 + bevacizumab and SOC arms was 3.7 months (95% confidence interval, 2.0–4.3) and 3.9 months (95% confidence interval 2.2–5.4), respectively (stratified log-rank P = 0.831). The objective response rate by IRR was 5% with CRLX101 + bevacizumab versus 14% with SOC (Mantel–Haenszel test, P = 0.836). Consistent with previous studies, the CRLX101 + bevacizumab combination was generally well tolerated, and no new safety signal was identified.ConclusionsDespite promising efficacy data on the earlier phase Ib/2 trial of mRCC, this randomized trial did not demonstrate improvement in PFS for the CRLX101 + bevacizumab combination when compared with approved agents in patients with heavily pretreated clear cell mRCC. Further development in this disease is not planned.Clinical trial identificationNCT02187302 (NIH).     

A phase I trial of dactinomycin intravenous infusion in patients with advanced malignancies

Eighteen patients with advanced malignancies refractory to other forms of treatment were given dactinomycin (Act D) as continuous intravenous infusions. Their median age was 51 years (range, 36-67); their median performance status was 50 (range, 40-90) on the Karnofsky scale. Act D was administered continuously for 5 days, utilizing a central venous line and a perfusion pump. The starting dose was 0.1 mg/m2/24 hours X 5 days (total dose, 0.5 mg/m2) and was escalated according to a modified Fibonacci scale to 0.2, 0.33, and 0.5 mg/m2/24 hours X 5 days, respectively. Three, three, four, and eight patients were entered, respectively, in each dose level. Toxicities observed were: leukopenia in four patients (nadir leukocyte count less than 1000 cells/nm3 in one patient and 2000-3000 cells/mm3 in 3 patients); thrombocytopenia, with nadir platelet counts between 50,000 and 100,000 platelets/mm3 in 2 patients; stomatitis in four patients; and nausea in three patients. Vomiting was not observed during the infusions. Two patients may have had a radiation recall phenomenon. Blood count depression, nausea, and mucositis were transient, resolving after a few days. One patient at level IV died of sepsis, which was diagnosed on the fourth day of the infusion, before leukopenia intervened. No objective responses were seen. It was concluded that a higher dose of Act D can be given by continuous infusion than by a bolus injection; the authors recommended 0.5 mg/m2/day X 5 days (total dose, 2.5 mg/m2) for further studies.     

Phase I trial of SU14813 in patients with advanced solid malignancies

Background: This phase I, open-label, dose-escalation study investigated SU14813, an oral multitargeted tyrosine kinase inhibitor, in adults with solid tumors.Patients and methods: Seventy-seven patients received once-daily SU14813, either for 4 weeks followed by 1 week off treatment (schedule 4/1) or continuously [continuous daily dosing (CDD)]. The primary end point was to determine the maximum tolerated dose (MTD). Safety, pharmacokinetics, pharmacodynamics, and efficacy were assessed.Results: MTDs were 200 mg/day on schedule 4/1 and 100 mg/day with CDD. Adverse events included fatigue (64%), diarrhea (61%), nausea (44%), anorexia (43%), and vomiting (42%). SU14813 steady state was attained by day 8. Exposure increased in a generally dose-proportional manner and SU14813 was eliminated with a mean terminal half-life of 9–34 h. Target plasma concentrations (>100 ng/ml SU14813) were achieved and sustained over 12 h at ≥100 mg/day. Progression-free survival among the 1 complete responder and 12 partial responders was 1.4–53.2 months. Fifteen patients remained on treatment at 1 year and 3 patients at 2 years.Conclusion: SU14813 has manageable safety and tolerability and allows once-daily continuous oral dosing. SU14813 shows dose-proportional pharmacokinetics, with target plasma concentrations achieved at doses ≥100 mg/day. Clinically meaningful activity with durable responses was observed, meriting further study.     

Sorafenib in patients with metastatic renal cell carcinoma refractory to either sunitinib or bevacizumab

BACKGROUND:

Bevacizumab and sunitinib are standard initial therapy in metastatic renal cell carcinoma (mRCC). Despite common use, the safety and activity of sorafenib in bevacizumab‐ or sunitinib‐refractory mRCC have not been prospectively investigated.

METHODS:

Metastatic RCC patients with Response Evaluation Criteria in Solid Tumors (RECIST)‐defined disease progression (PD) after treatment with either bevacizumab or sunitinib received twice daily 400 mg of sorafenib in a multicenter, prospective phase 2 study. Dose escalation was permitted in the absence of significant toxicity. The primary endpoint was tumor burden reduction rate, defined as the proportion of patients with ≥5% reduction in the sum of RECIST‐defined target lesions without other PD. Secondary endpoints included progression‐free survival (PFS), duration of response, overall survival, and safety. A 2‐stage accrual design was used to test the alternative hypothesis that the tumor burden reduction rate was >20% versus <5%.

RESULTS:

Forty‐eight patients were enrolled. The tumor burden reduction rate was 30% (95% confidence interval [CI], 17%‐45%). One unconfirmed objective partial response was observed. The median PFS was 4.4 months (95% CI, 3.6‐5.9). There was no association of PFS and tumor shrinkage with response to prior therapy. Most treatment‐related adverse events were of mild‐to‐moderate intensity, and included fatigue, hypertension, diarrhea, and palmoplantar erythrodysesthesia (PPE). Patients previously treated with bevacizumab tended to develop more PPE (P = .03) and mucositis (P = .06), whereas sunitinib‐treated patients tended to develop more skin rash (P = .06).

CONCLUSIONS:

Administration of sorafenib is safe and feasible in patients with mRCC refractory to either bevacizumab or sunitinib. Modest clinical activity was observed supporting current practice patterns of sequential vascular endothelial growth factor‐targeted therapy in mRCC. Cancer 2010. © 2010 American Cancer Society.     

A phase I/II trial of sorafenib and infliximab in advanced renal cell carcinoma

There is clinical evidence to suggest that tumour necrosis factor-α (TNF-α) may be a therapeutic target in renal cell carcinoma (RCC). Multi-targeted kinase inhibitors, such as sorafenib and sunitinib, have become standard of care in advanced RCC. The anti-TNF-α monoclonal antibody infliximab and sorafenib have differing cellular mechanisms of action. We conducted a phase I/II trial to determine the safety and efficacy of infliximab in combination with sorafenib in patients with advanced RCC. Eligible patients were systemic treatment-naive or had received previous cytokine therapy only. Sorafenib and infliximab were administered according to standard schedules. The study had two phases: in phase I, the safety and toxicity of the combination of full-dose sorafenib and two dose levels of infliximab were evaluated in three and three patients, respectively, and in phase II, further safety, toxicity and efficacy data were collected in an expanded patient population. Acceptable safety was reported for the first three patients (infliximab 5 mg kg⁻¹) in phase 1. Sorafenib 400 mg twice daily and infliximab 10 mg kg⁻¹ were administered to a total of 13 patients (three in phase 1 and 10 in phase 2). Adverse events included grade 3 hand–foot syndrome (31%), rash (25%), fatigue (19%) and infection (19%). Although manageable, toxicity resulted in 75% of the patients requiring at least one dose reduction and 81% requiring at least one dose delay of sorafenib. Four patients were progression-free at 6 months (PFS₆ 31%); median PFS and overall survival were 6 and 14 months, respectively. Sorafenib and infliximab can be administered in combination, but a significant increase in the numbers of adverse events requiring dose adjustments of sorafenib was observed. There was no evidence of increased efficacy compared with sorafenib alone in advanced RCC. The combination of sorafenib and infliximab does not warrant further evaluation in patients with advanced RCC.     

A phase I study of docetaxel and 5-fluorouracil in patients with advanced solid malignancies

Purpose: This study was undertaken to evaluate the feasibility of administering docetaxel (Taxotere; Rhône- Poulenc-Rorer) as a one-hour intravenous (i.v.) infusion on day 1 combined with 5-fluorouracil (5-FU) as a bolus i.v. injection for five (days 1–5) or three (days 1–3) consecutive days every four weeks.Patients and methods: Thirty-seven patients with advanced solid malignancies were treated with 115 total courses involving seven dose levels of the two regimens of docetaxel and 5-FU (docetaxel/5-FU [mg/m2]/mg/m2/d]). In an effort to reduce fluid retention and hypersensitivity phenomena related to docetaxel, patients received premedication with dexamethasone 8 mg orally twice daily for three consecutive days beginning 24 hours before treatment.Results: Severe (grade 4) neutropenia lasting longer than seven days with or without fever and/or severe mucositis, precluded further dose escalation above docetaxel 60 mg/m2 on day 1 and 5-FU 300 mg/m2/day administered on days 1–5 every four weeks. The rates of these toxic effects were also unacceptably high above docetaxel 60 mg/m2 on day 1 and 5- FU 300 mg/m2/day administered on days 1–3 every four weeks. Nine patients experienced various manifestations of fluid- retention that were potentially related to study drugs. However, neither treatment delay nor discontinuation of treatment was required. Nausea, vomiting, diarrhea, and fatigue, were mild to modest in severity and occurred infrequently (<10% of courses). Two patients with metastatic breast cancer experienced complete responses and a partial response occurred in a patient with metastatic non-small-cell lung cancer.Conclusion: Based on the results of this study, the regimen of docetaxel 60 mg/m2 on day 1 followed by 5-FU 300 mg/m2/d i.v. for three or five days every four weeks is well tolerated and these doses are recommended for further evaluations. The feasibility of administering docetaxel 60 mg/m2 followed by 5-FU 300 mg/m2 for three or five days every four weeks and the preliminary antitumor activity noted indicate that further disease-directed studies of docetaxel and 5-FU are warranted in patients with relevant solid malignancies.     

A phase I and pharmacodynamic evaluation of polyethylene glycol-conjugated L-asparaginase in patients with advanced solid tumors

PURPOSE: To evaluate the in vitro activity of polyethylene glycol-conjugated L-asparaginase (PEG-Lasparaginase) against fresh human tumor specimens, using the human tumor clonogenic assay (HTCA), and to perform a phase I dose-escalation clinical trial of PEG-L-asparaginase. The goal of the clinical study was to determine the toxicity and optimum biologic dose of PEG-L-asparaginase based on depletion of serum L-asparagine in patients with advanced solid tumors. METHODS: A modified method for determination of serum L-asparagine is described. PEG-L-asparaginase was administered by intramuscular injection every 2 weeks to 28 patients with various types of advanced solid tumor malignancies. At least 3 patients were evaluated at each dose level: 250 IU/m2, 500 IU/m2, 1,000 IU/m2, 1,500 IU/m2, 2,000 IU/m2. RESULTS: The in vitro HTCA studies suggested good antitumor activity against malignant melanoma and multiple myeloma. Serum L-asparagine was most consistently and profoundly depleted (up to 4 weeks) in patients treated with 2,000 IU/m2. Patients receiving this dose level also showed more frequent grade 1, grade 2, and occasional grade 3 toxicities of fatigue/weakness, nausea/vomiting, and anorexia/ weight loss. Three patients developed hypersensitivity reactions, but these were not dose related. Two patients developed deep vein thromboses. We saw no episodes of clinical pancreatitis, but there were minor fluctuations of serum amylase and lipase. We saw no partial or complete responses in patients treated in this study, including 11 patients with malignant melanoma. CONCLUSIONS: We conclude that PEG-L-asparaginase is generally well tolerated in patients with advanced solid tumors, and a dosage of 2,000 IU/m2 by intramuscular injection every 2 weeks results in significant depletion of serum L-asparagine.     

A phase I pharmacodynamic trial of bortezomib in combination with doxorubicin in patients with advanced cancer

Purpose  This phase I trial sought to define the toxicity, maximally tolerated dose (MTD) and pharmacodynamics of a combination of bortezomib and doxorubicin in patients with advanced malignancies. Patients and methods  Twenty-six patients were treated with bortezomib intravenously on days 1, 4, 8 and 11, with doxorubicin also administered intravenously on days 1 and 8, both in a 21-day cycle. Dosing ranged from 1.0 mg/m² of bortezomib with 15 mg/m² of doxorubicin to 1.5 mg/m² of bortezomib with 20 mg/m² of doxorubicin. Pharmacodynamic studies performed included assessment of levels of 20S proteasome activity and ubiquitin-protein conjugates. Results  The combination of bortezomib and doxorubicin was generally well tolerated. There were two dose limiting toxicities (DLT) at dose cohort 3 (1.3 mg/m² bortezomib, 20 mg/m² doxorubicin) and 2 DLT at dose cohort 3a (1.5 mg/m² bortezomib, 15 mg/m² doxorubicin). DLT seen included neutropenia, thrombocytopenia, and neuropathy. In addition, one patient developed grade 3 central nervous system toxicity in cycle 2 (not a DLT). One patient with hormone refractory prostate cancer had a partial response. Proteasome inhibition in whole blood was demonstrated and an increase in ubiquitin-protein conjugates was observed in peripheral blood mononuclear cells of most patients. Conclusions  Bortezomib and doxorubicin can be administered safely. The recommended phase II dose for this 21-day cycle is bortezomib 1.3 mg/m² intravenously on days 1, 4, 8 and 11, and doxorubicin 20 mg/m² intravenously on days 1 and 8. This combination may be of special interest in multiple myeloma, given the activity of both drugs in that disease. Supported by grant: U01 CA062491 “Early Clinical Trials of Anti-Cancer Agents With Phase I Emphasis, NCI” and M01 RR03186 “General Clinical Research Center Program of The National Center for Research Resources, NIH”.     

A phase I study of sunitinib combined with modified FOLFOX6 in patients with advanced solid tumors

Purpose

This phase I study assessed the safety, tolerability, maximum tolerated dose (MTD), pharmacokinetics, and preliminary antitumor effects of sunitinib combined with modified FOLFOX6 (mFOLFOX6).

Methods

Patients with advanced solid malignancies received mFOLFOX6 in 2-week cycles with escalating sunitinib doses (25, 37.5, and 50?mg/day) on three schedules: 2?weeks on, 2?weeks off (2/2); 4?weeks on, 2?weeks off (4/2); or continuous daily dosing (CDD). Patients received up to 8 treatment cycles (Schedule 2/2 and CDD schedule) or 6 cycles (Schedule 4/2). An expansion cohort enrolled patients with metastatic colorectal cancer at the Schedule 2/2 MTD.

Results

Overall, 53 patients were enrolled, with 43 evaluable for dose-limiting toxicity (DLT). On Schedule 2/2 (n?=?18), DLTs occurred in three patients at 50?mg/day (grade 4 neutropenia [n?=?1]; grades 3 and 4 thrombocytopenia [n?=?2]) and two patients achieved partial responses (PRs). On Schedule 4/2 (n?=?13), 37.5?mg/day exceeded the MTD with two DLTs (febrile neutropenia and grade 4 hypokalemia, respectively). On the CDD schedule (n?=?12), the MTD was 25?mg/day; one DLT (grade 3 stomatitis) was reported and two patients achieved PRs. The most common adverse events were neutropenia, fatigue, and thrombocytopenia. No clinically significant drug?Cdrug interactions were apparent between sunitinib, its metabolite SU12662, and mFOLFOX6.

Conclusions

Sunitinib combined with mFOLFOX6 had acceptable tolerability. The MTDs were sunitinib 50?mg/day on Schedule 2/2 and 25?mg/day on the CDD schedule. A MTD for Schedule 4/2 was not established.     

A phase I dose-escalation and pharmacokinetic study of sunitinib in combination with pemetrexed in patients with advanced solid malignancies, with an expanded cohort in non-small cell lung cancer

Purpose

The primary objective of this phase I dose-escalation study was to identify the maximum tolerated dose (MTD) of sunitinib plus pemetrexed in patients with advanced cancer.

Methods

Using a 3?+?3 dose-escalation design, patients received oral sunitinib qd by continuous daily dosing (CDD schedule; 37.5 or 50?mg) or 2?weeks on/1?week off treatment schedule (Schedule 2/1; 50?mg). Pemetrexed (300?C500?mg/m² IV) was administered q3w. At the proposed recommended phase 2 dose (RP2D), additional patients with non-small cell lung cancer (NSCLC) were enrolled.

Results

Thirty-five patients were enrolled on the CDD schedule and seven on Schedule 2/1. MTDs were sunitinib 37.5?mg/day (CDD/RP2D) or 50?mg/day (Schedule 2/1) with pemetrexed 500?mg/m². Dose-limiting toxicities included grade (G) 5 cerebral hemorrhage, G3 febrile neutropenia, and G3 anorexia. Common G3/4 drug-related non-hematologic adverse events (AEs) at the CDD MTD included fatigue, anorexia, and hand?Cfoot syndrome. G3/4 hematologic AEs included lymphopenia, neutropenia, and thrombocytopenia. No significant drug?Cdrug interactions were identified. Five (24%) NSCLC patients had partial responses.

Conclusions

In patients with advanced solid malignancies, the MTD of sunitinib plus 500?mg/m² pemetrexed was 37.5?mg/day (CDD schedule) or 50?mg/day (Schedule 2/1). The CDD schedule MTD was tolerable and demonstrated promising clinical benefit in NSCLC.     

Treatment of advanced renal cell carcinoma with the combination bevacizumab/erlotinib/imatinib: a phase I/II trial

PURPOSE: The aim of this study was to evaluate the efficacy and toxicity of imatinib, a platelet-derived growth factor-beta receptor antagonist, when added to the combination bevacizumab/erlotinib in the treatment of patients with advanced clear cell renal carcinoma. PATIENTS AND METHODS: Ninety-four patients with metastatic clear cell renal carcinoma were treated with bevacizumab 10 mg/kg intravenously every 2 weeks, erlotinib 150 mg orally daily, and imatinib 400 mg orally daily. Patients were reevaluated after 8 weeks of treatment; patients with objective response or stable disease (SD) continued to receive treatment until they experienced tumor progression. RESULTS: Fifteen of 88 evaluable patients (17%; 95% confidence interval, 10%-26%) had partial responses, whereas an additional 54 patients (61%) had SD. The median progression-free and overall survival for all patients was 8.9 months and 17.2 months, respectively. The addition of imatinib markedly increased toxicity compared with the bevacizumab/erlotinib regimen; the most common grade 3/4 toxicities were diarrhea, rash, and fatigue. CONCLUSION: Bevacizumab/erlotinib/imatinib was unacceptably toxic in this group of patients. Inhibition of the PDGF receptor (PDGFR) with imatinib did not appear to improve efficacy compared retrospectively with the results of treatment with bevacizumab/erlotinib. The importance of PDGFR inhibition in the treatment of advanced clear cell renal carcinoma remains unclear. Further development of this particular combination is not planned or recommended.     

A phase I trial of perillyl alcohol in patients with advanced solid tumors

PURPOSE: Perillyl alcohol is a plant-derived lipid with preclinical antitumor activity. Its proposed mechanism of action involves inhibition of post-translational isoprenylation of small G proteins, including the proto-oncogene p21- ras, thereby blocking signal transduction. This phase I trial was conducted to determine the optimal dose of perillyl alcohol. METHODS: The study group comprised 21 adults with advanced solid tumors who were treated with perillyl alcohol, delivered orally, four times daily, without interruption. Doses ranged from 4,800 to 11,200 mg/m(2) per day. RESULTS: The maximum tolerated dose (MTD) for this schedule was determined to be 8400 mg/m(2) per day. The dose-limiting toxicities in this trial were nausea and vomiting, encountered in all patients at the highest dose level. No antitumor activity was observed. Pharmacokinetic data suggest dose-dependent increases in C(max) of perillic acid, a metabolite of perillyl alcohol, but with high inter- and intrapatient variability. CONCLUSIONS: The MTD of perillyl alcohol for this schedule was determined to be 8400 mg/m(2) per day. This is higher than the MTDs determined in other similar phase I trials. This may have been due to the fact that the gastrointestinal symptoms caused by perillyl alcohol are highly subjective, with high interpatient variability. Phase II trials of perillyl alcohol in hormone-refractory prostate, breast, ovarian and colorectal cancer using doses in the range 4800-6400 mg/m(2) per day are underway.