Biosimilar Use Among 38 ASCO PracticeNET Practices, 2019-2021.

PURPOSE: Biosimilars offer increased patient choice and potential cost-savings, compared with originator biologics. We studied 3 years of prescribed biologics among US physician practices to determine the relationship of practice type and payment source to oncology biosimilar use. METHODS: We acquired biologic utilization data from 38 practices participating in PracticeNET. We focused on six biologics (bevacizumab, epoetin alfa, filgrastim, pegfilgrastim, rituximab, and trastuzumab) for the period from 2019 to 2021. We complemented our quantitative analysis with a survey of PracticeNET participants (prescribers and practice leaders) to reveal potential motivators and barriers to biosimilar use. We implemented logistic regression to evaluate the biosimilar use for each biologic, with covariates including time, practice type, and payment source, and accounted for clusters of practices. RESULTS: Use of biosimilars increased over the 3-year period, reaching between 51% and 80% of administered doses by the fourth quarter of 2021, depending on the biologic. Biosimilar use varied by practice, with independent physician practices having higher use of biosimilars for epoetin alfa, filgrastim, rituximab, and trastuzumab. Compared with commercial health plans, Medicaid plans had lower biosimilar use for four biologics; traditional Medicare had lower use for five biologics. The average cost per dose decreased between 24% and 41%, dependent on the biologic. CONCLUSION: Biosimilars have, through increased use, lowered the average cost per dose of the studied biologics. Biosimilar use differed by originator biologic, practice type, and payment source. There remains further opportunity for increases in biosimilar use among certain practices and payers.

A Review of Concurrent Chemo/Radiation, Immunotherapy, Radiation Planning, and Biomarkers for Locally Advanced Non-small Cell Lung Cancer and Their Role in the Development of ECOG-ACRIN EA5181.

ECOG-ACRIN EA5181 is a current prospective, randomized trial that is investigating whether the addition of concomitant durvalumab to standard chemo/radiation followed by 1 year of consolidative durvalumab results in an overall survival benefit over standard chemo/radiation alone followed by 1 year of consolidative durvalumab in patients with locally advanced, unresectable non-small cell lung cancer (NSCLC). Because multiple phase I/II trials have shown the relative safety of adding immunotherapy to chemo/radiation and due to the known synergism between chemotherapy and immunotherapy, it is hoped that concomitant durvalumab can reduce the relatively high incidence of local failure (38%-46%) as seen in recent prospective, randomized trials of standard chemo/radiation in this patient population. We will review the history of radiation for LA-NSCLC and discuss the role of induction, concurrent and consolidative chemotherapy as well as the concerns for late cardiac and pulmonary toxicities associated with treatment. Furthermore, we will review the potential role of next generation sequencing, PD-L1, ctDNA and tumor mutation burden and their possible impact on this trial.

A Review of Immunotherapy for Stage III and Metastatic Non-Small Cell Lung Cancer and the Rationale for the ECOG-ACRIN EA5181 Study.

ECOG-ACRIN EA5181 is a phase III prospective, randomized trial that randomizes patients undergoing chemo/radiation for locally advanced non-small cell lung cancer (LA-NSCLC) to concomitant durvalumab or no additional therapy, with both arms receiving 1 year of consolidative durvalumab. Radiation dose escalation failed to improve overall survival in RTOG 0617. However, conventionally fractionated radiation to 60 Gy with concomitant chemotherapy is associated with a high risk of local failure (38%-46%). It is hoped that concomitant immunotherapy during chemo/radiation can help decrease the risk of local failure, thereby improving overall survival and progression-free survival with acceptable toxicity. In this article, we review conventional chemo/radiation therapy for LA-NSCLC, as well as the quickly evolving world of immunotherapy in the treatment of non-small cell lung cancer and discuss the rationale and study design of EA5181. IMPLICATIONS FOR PRACTICE: This article provides an up-to-date assessment of how immunotherapy is reshaping the landscape of metastatic non-small cell lung cancer (NSCLC) and how the impact of this therapy is now rapidly moving into the treatment of patients with locally advanced NSCLC who are presenting for curative treatment. This article reviews the recent publications of chemo/radiation as well as those combining immunotherapy with chemotherapy and chemo/radiation, and provides a strategy for improving overall survival of patients with locally advanced NSCLC by using concomitant immunotherapy with standard concurrent chemo/radiation.

Benchmarks for Academic Oncology Faculty.

The role of clinical researchers is vital to cancer progress. The teaching, research, and leadership roles that academic oncologists hold need to be accounted for and appropriately compensated. National metrics are currently inexistent, but are necessary to move the oncology research field forward. Clinical research and routine clinical care must be harmoniously integrated without competing. This article reviews the national landscape of clinical cancer research and proposes a call for action.

American Society of Clinical Oncology Road to Recovery Report: Learning From the COVID-19 Experience to Improve Clinical Research and Cancer Care.

This report presents the American Society of Clinical Oncology's (ASCO's) evaluation of the adaptations in care delivery, research operations, and regulatory oversight made in response to the coronavirus pandemic and presents recommendations for moving forward as the pandemic recedes. ASCO organized its recommendations for clinical research around five goals to ensure lessons learned from the COVID-19 experience are used to craft a more equitable, accessible, and efficient clinical research system that protects patient safety, ensures scientific integrity, and maintains data quality. The specific goals are: (1) ensure that clinical research is accessible, affordable, and equitable; (2) design more pragmatic and efficient clinical trials; (3) minimize administrative and regulatory burdens on research sites; (4) recruit, retain, and support a well-trained clinical research workforce; and (5) promote appropriate oversight and review of clinical trial conduct and results. Similarly, ASCO also organized its recommendations regarding cancer care delivery around five goals: (1) promote and protect equitable access to high-quality cancer care; (2) support safe delivery of high-quality cancer care; (3) advance policies to ensure oncology providers have sufficient resources to provide high-quality patient care; (4) recognize and address threats to clinician, provider, and patient well-being; and (5) improve patient access to high-quality cancer care via telemedicine. ASCO will work at all levels to advance the recommendations made in this report.

Lenalidomide and dexamethasone in patients with relapsed multiple myeloma and impaired renal function: PrE1003, a PrECOG study.

Renal insufficiency is common in patients with relapsed multiple myeloma and can often limit choice of therapy. Lenalidomide, a critical agent in the treatment of relapsed multiple myeloma, is renally cleared., This phase I/II trial evaluated the efficacy and safety of lenalidomide with dexamethasone in patients with relapsed multiple myeloma and renal insufficiency. Three groups were treated, with creatinine clearance 30-60 cc/hr (group A), CrCl < 30 not on dialysis (group B), and patients on dialysis (group C) at escalating doses of lenalidomide. A total of 63 patients were treated and no DLTs were observed in phase I. All three groups were able to escalate to full dose lenalidomide 25 mg daily 21/28 days, although due to reduced accrual the phase II component was not entirely completed for groups B and C. Adverse events were as expected, including anemia, diarrhea and fatigue. Ten patients experienced grade 3-4 pneumonia. Overall response rate was 54% across all groups. PFS was 7.5 months and OS was 19.7 months. Lenalidomide can be given at full dose 25 mg daily 21/28 in patients with a CrCl > 30, and can be given daily to those with CrCl < 30, even when on dialysis, at doses of at least 15 mg daily.

Cetuximab plus carboplatin and paclitaxel with or without bevacizumab versus carboplatin and paclitaxel with or without bevacizumab in advanced NSCLC (SWOG S0819): a randomised, phase 3 study.

BACKGROUND: EGFR antibodies have shown promise in patients with advanced non-small-cell lung cancer (NSCLC), particularly with squamous cell histology. We hypothesised that EGFR copy number by fluorescence in-situ hybridisation (FISH) can identify patients most likely to benefit from these drugs combined with chemotherapy and we aimed to explore the activity of cetuximab with chemotherapy in patients with advanced NSCLC who are EGFR FISH-positive. METHODS: We did this open-label, phase 3 study (SWOG S0819) at 277 sites in the USA and Mexico. We randomly assigned (1:1) eligible patients with treatment-naive stage IV NSCLC to receive paclitaxel (200 mg/m2; every 21 days) plus carboplatin (area under the curve of 6 by modified Calvert formula; every 21 days) or carboplatin plus paclitaxel and bevacizumab (15 mg/kg; every 21 days), either with cetuximab (250 mg/m2 weekly after loading dose; cetuximab group) or without (control group), stratified by bevacizumab treatment, smoking status, and M-substage using a dynamic-balancing algorithm. Co-primary endpoints were progression-free survival in patients with EGFR FISH-positive cancer and overall survival in the entire study population. We analysed clinical outcomes with the intention-to-treat principle and analysis of safety outcomes included patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov (number NCT00946712). FINDINGS: Between Aug 13, 2009, and May 30, 2014, we randomly assigned 1313 patients to the control group (n=657; 277 with bevacizumab and 380 without bevacizumab in the intention-to-treat population) or the cetuximab group (n=656; 283 with bevacizumab and 373 without bevacizumab in the intention-to-treat population). EGFR FISH was assessable in 976 patients and 400 patients (41%) were EGFR FISH-positive. The median follow-up for patients last known to be alive was 35·2 months (IQR 22·9-39·9). After 194 progression-free survival events in the cetuximab group and 198 in the control group in the EGFR FISH-positive subpopulation, progression-free survival did not differ between treatment groups (hazard ratio [HR] 0·92, 95% CI 0·75-1·12; p=0·40; median 5·4 months [95% CI 4·5-5·7] vs 4·8 months [3·9-5·5]). After 570 deaths in the cetuximab group and 593 in the control group, overall survival did not differ between the treatment groups in the entire study population (HR 0·93, 95% CI 0·83-1·04; p=0·22; median 10·9 months [95% CI 9·5-12·0] vs 9·2 months [8·7-10·3]). In the prespecified analysis of EGFR FISH-positive subpopulation with squamous cell histology, overall survival was significantly longer in the cetuximab group than in the control group (HR 0·58, 95% CI 0·36-0·86; p=0·0071), although progression-free survival did not differ between treatment groups in this subgroup (0·68, 0·46-1·01; p=0·055). Overall survival and progression-free survival did not differ among patients who were EGFR FISH non-positive with squamous cell histology (HR 1·04, 95% CI 0·78-1·40; p=0·77; and 1·02, 0·77-1·36; p=0·88 respectively) or patients with non-squamous histology regardless of EGFR FISH status (for EGFR FISH-positive 0·88, 0·68-1·14; p=0·34; and 0·99, 0·78-1·27; p=0·96; respectively; and for EGFR FISH non-positive 1·00, 0·85-1·17; p=0·97; and 1·03, 0·88-1·20; p=0·69; respectively). The most common grade 3-4 adverse events were decreased neutrophil count (210 [37%] in the cetuximab group vs 158 [25%] in the control group), decreased leucocyte count (103 [16%] vs 74 [20%]), fatigue (81 [13%] vs 74 [20%]), and acne or rash (52 [8%] vs one [<1%]). 59 (9%) patients in the cetuximab group and 31 (5%) patients in the control group had severe adverse events. Deaths related to treatment occurred in 32 (6%) patients in the cetuximab group and 13 (2%) patients in the control group. INTERPRETATION: Although this study did not meet its primary endpoints, prespecified subgroup analyses of patients with EGFR FISH-positive squamous-cell carcinoma cancers are encouraging and support continued evaluation of anti-EGFR antibodies in this subpopulation. FUNDING: National Cancer Institute and Eli Lilly and Company.

Are We on the Same Page? Patient and Provider Perceptions About Exercise in Cancer Care: A Focus Group Study.

Background: Physical activity (PA) during and after cancer treatment can help with symptom management and reduce the risk of cancer recurrence. However, it is unclear what constitutes an optimal exercise program. In addition, provider and patient barriers exist to the recommendation and adoption of exercise as part of a cancer treatment plan. The goal of this study was to determine how providers and patients feel about exercise during cancer treatment and explore what the barriers to implementing such a program might be. Patients and Methods: Focus groups and interviews were held with patients with malignancy, both metastatic and nonmetastatic, and oncology providers. In total, 20 patients participated in either a focus group or an individual interview and 9 providers contributed to the focus group. An equal number of patients (n=10) were interviewed as attended a focus group. Audiotaped sessions were transcribed verbatim. Theme identification was independently coded by 4 coders and synthesized as a group. Results: Neither patient group recalled PA instruction from oncology providers during their cancer treatment. Most participants (95%) felt exercise is important during cancer treatment, citing overall well-being benefits versus improved disease outcome. Most patients (80%) preferred a home-based exercise program provided by the oncologist. Fatigue was the most cited barrier to regular exercise during treatment (50%). All providers acknowledged benefits of PA to patients, but not universally for all. More than half of providers (55%) preferred a referral system for exercise programs. Clinic visit time constraints and a perceived lack of expertise in the area of PA were common barriers to making exercise recommendations a routine part of the treatment plan. Conclusions: Patients with cancer and oncologists recognize the benefits of PA during treatment. Disagreement exists between to whom, how, and where exercise plans should be disseminated and implemented.

Vorinostat and bortezomib as third-line therapy in patients with advanced non-small cell lung cancer: a Wisconsin Oncology Network Phase II study.

INTRODUCTION: The primary objective of this phase II trial was to evaluate the efficacy and tolerability of vorinostat and bortezomib as third-line therapy in advanced non-small cell lung cancer (NSCLC) patients. METHODS: Eligibility criteria included recurrent/metastatic NSCLC, having received 2 prior systemic regimens, and performance status 0-2. Patients took vorinostat 400 mg PO daily days 1-14 and bortezomib 1.3 mg/m2 IV day 1, 4, 8 and 11 in a 21-day cycle. Primary endpoint was 3-month progression free survival (3m-PFS), with a goal of at least 40 % of patients being free of progression at that time point. This study followed a two-stage minimax design. RESULTS: Eighteen patients were enrolled in the first stage. All patients had two prior lines of treatment. Patients received a median of two treatment cycles (range: 1-6) on study. There were no anti-tumor responses; stable disease was observed in 5 patients (27.8 %). Median PFS was 1.5 months, 3m-PFS rate 11.1 %, and median overall survival 4.7 months. The most common grade 3/4 toxicities were thrombocytopenia and fatigue. Two patients who had baseline taxane-related grade 1 peripheral neuropathy developed grade 3 neuropathy. The study was closed at its first interim analysis for lack of efficacy. CONCLUSIONS: Bortezomib and vorinostat displayed minimal anti-tumor activity as third-line therapy in NSCLC. We do not recommend this regimen for further investigation in unselected patients.

Nuclear EGFR protein expression predicts poor survival in early stage non-small cell lung cancer.

INTRODUCTION: Nuclear EGFR (nEGFR) has been identified in various human tumor tissues, including cancers of the breast, ovary, oropharynx, and esophagus, and has predicted poor patient outcomes. We sought to determine if protein expression of nEGFR is prognostic in early stage non-small cell lung cancer (NSCLC). METHODS: Resected stages I and II NSCLC specimens were evaluated for nEGFR protein expression using immunohistochemistry (IHC). Cases with at least one replicate core containing ≥5% of tumor cells demonstrating strong dot-like nucleolar EGFR expression were scored as nEGFR positive. RESULTS: Twenty-three (26.1% of the population) of 88 resected specimens stained positively for nEGFR. Nuclear EGFR protein expression was associated with higher disease stage (45.5% of stage II vs. 14.5% of stage I; p = 0.023), histology (41.7% in squamous cell carcinoma vs. 17.1% in adenocarcinoma; p = 0.028), shorter progression-free survival (PFS) (median PFS 8.7 months [95% CI 5.1-10.7 mo] for nEGFR positive vs. 14.5 months [95% CI 9.5-17.4 mo] for nEGFR negative; hazard ratio (HR) of 1.89 [95% CI 1.15-3.10]; p = 0.011), and shorter overall survival (OS) (median OS 14.1 months [95% CI 10.3-22.7 mo] for nEGFR positive vs. 23.4 months [95% CI 20.1-29.4 mo] for nEGFR negative; HR of 1.83 [95% CI 1.12-2.99]; p = 0.014). CONCLUSIONS: Expression of nEGFR protein was associated with higher stage and squamous cell histology, and predicted shorter PFS and OS, in this patient cohort. Nuclear EGFR serves as a useful independent prognostic variable and as a potential therapeutic target in NSCLC.

A phase I study of sorafenib, oxaliplatin and 2 days of high dose capecitabine in advanced pancreatic and biliary tract cancer: a Wisconsin oncology network study.

Chemotherapy has yielded minimal clinical benefit in pancreatic and biliary tract cancer. A high-dose, short course capecitabine schedule with oxaliplatin, has shown some efficacy with a lower incidence of palmar-plantar erythrodysesthesia. Achieving high exposures of the targeted agent sorafenib may be possible with this shorter schedule of capecitabine by avoiding dermatologic toxicity. All patients had pancreatic or biliary tract cancer. Patients in both cohorts received oxaliplatin 85 mg/m2 followed by capecitabine 2,250 mg/m2 PO every 8 h x 6 doses starting on days 1 and 15 of a 28 day cycle, or 2DOC (2 Day Oxaliplatin/Capecitabine). Cohort 1 used sorafenib 200 mg BID, and cohort 2 used sorafenib 400 mg BID. Sixteen patients were enrolled. Across all cycles the most common grade 1 or 2 adverse events were fatigue (10 pts), diarrhea (10 pts), nausea (9 pts), vomiting (8 pts), sensory neuropathy (8 pts), thrombocytopenia (7 pts), neutropenia (5 pts), and hand-foot syndrome (5 pts). Grade 3 toxicites included neutropenia, mucositis, fatigue, vomiting and diarrhea. Cohort 1 represented the MTD. Two partial responses were seen, one each in pancreatic and biliary tract cancers. The recommended phase II dose of sorafenib in combination with 2DOC is 200 mg BID. There were infrequent grade 3 toxicities, most evident with sorafenib at 400 mg BID.

Phase I/II study of vinorelbine and exisulind as first-line treatment of advanced non-small cell lung cancer in patients at least 70 years old: a wisconsin oncology network study.

INTRODUCTION: Exisulind is an apoptotic agent with preclinical activity in non-small cell lung cancer (NSCLC). Vinorelbine is safe and effective in older patients with advanced NSCLC. We assessed these agents together as palliative treatment for older patients with advanced NSCLC. METHODS: Chemotherapy-naive patients >/=70-years-old with stage IIIB-IV NSCLC and a performance status (PS) /=3 neutropenia occurred in 14/30 patients. Two patients experienced neutropenic fever. There were no complete responses, one partial response and 12 patients with stable disease as their best response. The objective response rate was 4.0% (95% CI: 0.1-20.4%). Phase II median time-to-progression was 4.7 months (95% CI: 3.1-9.3 months) and median OS was 9.6 months (95% CI: 6.6-19.1 months). CONCLUSIONS: This combination is safe, seems to have activity in the elderly with advanced NSCLC and a PS

Effect of medical castration on CYP3A4 enzyme activity using the erythromycin breath test.

PURPOSE: Testosterone administration can lead to increased antipyrine clearance in humans. Medical or surgical castration is a standard treatment of progressive prostate carcinoma, but the effect of the subsequent fall of testosterone concentrations upon drug metabolism has not been reported. METHODS: Eleven men with a biopsy-proven diagnosis of progressive prostate cancer were enrolled after providing informed consent. CYP3A4 activity was determined using the erythromycin breath test (EBT) in each patient prior to their beginning with an LHRH-agonist (leuprolide or goserelin). No patients had elected to undergo orchiectomy during the period of subject accrual. Each subject underwent a second EBT 2 months after beginning LHRH suppression. Blood samples were collected at these time points to determine changes in testosterone and leutinizing hormone. RESULTS: All subjects had a predictable drop in serum testosterone concentrations over the 8-week course of the study, but concentrations in three did not fall below castrate levels (<50 ng/dl). There was no statistically significant change in CYP3A4 activity using the EBT method (p = 0.88). The extent and direction of changes in CYP3A4 activity was highly variable, with three subjects experiencing an increase in activity, and five demonstrating a decrease in activity. CONCLUSION: There is no clinically significant change in CYP3A4 activity after medical castration. No changes in the clearance of docetaxel or other CYP3A4 substrates are likely during and after medical castration. Although similar findings are expected after orchiectomy, we were not able to test this presumption because of patient preference for medical castration.

Phase II study of interferon-alpha and doxycycline for advanced renal cell carcinoma.

OBJECTIVE: To assess the efficacy and toxicity of the combination of interferon-alpha and doxycycline in patients with metastatic renal cell carcinoma and to assess the effect of this treatment on serum vascular endothelial growth factor (VEGF) levels. PATIENTS AND METHODS: Seventeen patients with Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 and life expectancy greater than 4 months with radiologically evident advanced renal cell carcinoma were enrolled. Eight patients had prior nephrectomy and 10 patients were treated within 4 months of their diagnosis. Treatment consisted of interferon-alpha up to 9 million units subcutaneously three times per week and doxycycline 300 mg orally twice per day for weeks one and three of each four-week cycle. Toxicity was evaluated on a biweekly basis and response on a bimonthly basis. VEGF plasma levels were assessed monthly as a measure of potential antiangiogenic effect. RESULTS: No objective responses were seen. The mean duration of study was 2.6 cycles (range: 0.8-6.0 cycles). Three patients (17%) tolerated therapy and displayed stable disease for greater than four months. Five patients withdrew from study before the first response evaluation. Ten patients experienced grade 2 gastrointestinal toxicity requiring dose reduction of doxycycline. Eight patients experienced grade 2 fatigue requiring dose reduction of interferon. VEGF plasma levels were initially suppressed in patients who demonstrated progressive disease but not in patients with stable disease. CONCLUSION: This regimen of doxycycline and interferon-alpha was not efficacious as treatment for renal cell carcinoma. Plasma VEGF levels were significantly decreased during the first two cycles of treatment, but this does not correlate with clinical outcome.

Phase I/II study of gemcitabine and exisulind as second-line therapy in patients with advanced non-small cell lung cancer.

BACKGROUND: The study was designed to evaluate the safety and efficacy of exisulind, a selective apoptotic antineoplastic drug, in combination with gemcitabine as second-line therapy in patients with progressing advanced non-small cell lung cancer. METHODS: Patients whose disease progressed more than 3 months from completion of first-line chemotherapy were eligible for this phase I/II trial. Primary end points were maximally tolerated dose and time to progression. Patients in the phase I portion of the study were treated with gemcitabine (1250 mg/m) in combination with three escalated dose levels of exisulind. Treatment involved six cycles of gemcitabine and exisulind followed by exisulind maintenance. The study was subsequently expanded to phase II. RESULTS: Thirty-nine patients (15 in phase I and 24 in phase II) were treated. The regimen was well tolerated with grade 3 fatigue and grade 3 constipation being dose-limiting toxicities. The maximally tolerated dose was not reached. Dose level 3 of exisulind (250 mg twice daily) in combination with gemcitabine was used for phase II. The overall response rates were 7% (phase I), 17% (phase II), and 13% (all). Median time to progression and median and 1-year survival, respectively, were 3.7 and 9.7 months and 33% (phase I); 4.3 and 9.4 months and 41% (phase II); and 4.1 and 9.4 months and 39% (all). CONCLUSION: Although the study met its primary end point of improving time to progression (more than 4.1 months in phase II), we did not observe a clear survival advantage and thus do not plan to further investigate this schedule of gemcitabine and exisulind.

Phase II trial of perillyl alcohol (NSC 641066) administered daily in patients with metastatic androgen independent prostate cancer.

OBJECTIVE: We conducted a phase II multicenter trial of perillyl alcohol in patients with advanced hormone refractory prostate cancer (HRPC). The primary endpoint was to evaluate the 6-month progression-free survival given the potential cytostatic nature of the drug. Secondary objectives included assessing acute and chronic toxicities, as well as measuring objective response rates. METHODS: Patients with metastatic androgen-independent prostate cancer that failed at least one prior chemotherapeutic or experimental regimen were eligible. Perillyl alcohol was administered orally at 1200 mg/m2/dose four times daily and continued until disease progression or development of unacceptable toxicity. RESULTS: Fifteen patients were eligible. Six patients received less than one cycle (4 weeks) of drug, four of which stopped because of drug intolerance. Only six patients received more than two cycles of therapy and were considered evaluable for response. Main toxicity included grade 1-2 gastrointestinal intolerance (nausea/vomiting in 60% of the patients) and fatigue (47%). One patient developed a grade 4 hypokalemia that was felt likely attributable to the drug. No objective responses were seen. All patients either progressed or withdrew from the study secondary to drug intolerance before the 6-month time period. CONCLUSION: Perillyl alcohol administered at this dose and formulation did not have any objective clinical activity in this patient population.

Phase I trial of 1alpha-hydroxyvitamin d(2) in patients with hormone refractory prostate cancer.

This Phase I study of 1alpha-hydroxyvitamin D(2), an p.o. administered vitamin D analogue, in patients with advanced hormone-refractory prostate cancer was designed to assess the toxicity, pharmacokinetic and biological markers of drug activity, and lastly tumor response data to recommend a dose for Phase II studies. 1alpha-Hydroxyvitamin D(2) was administered daily at doses ranging from 5 to 15 microg/day. Patients were monitored for toxicity and tumor response, and blood and urine samples were collected for pharmacokinetics (1alpha,25-dihydroxyvitamin D(2) levels) and other parameters of biological activity (bone markers, parathyroid hormone, urine calcium, and serum phosphorus levels). Twenty-five patients were enrolled. Main toxicities were hypercalcemia with associated renal insufficiency. No other significant toxicity was seen. Pharmacokinetics showed an increase in the active metabolite 1alpha,25-dihydroxyvitamin D(2) that reached a plateau by week 4 despite continuous drug dosing. Elevation in daily urinary calcium excretion and serum phosphorus levels was seen, whereas a decrease in serum parathyroid hormone was evident. Two patients showed evidence of a partial response, whereas 5 others achieved disease stabilization for > or =6 months. 1alpha-Hydroxyvitamin D(2) was well tolerated with main toxicities being hypercalcemia and renal insufficiency. All of the toxicity was reversible with drug discontinuation. Evidence for drug activity was seen in surrogate markers, and pharmacokinetic analysis showed substantial increases in vitamin D metabolite levels among the various cohorts. Whereas the defined maximum tolerated dose was not reached, the recommended Phase II dose was 12.5 microg/day given continuously.