bropirimine and Neoplasms

Bropirimine (U-54461S), an oral interferon (IFN) inducer that has also a direct antiproliferative activity, is a novel antitumor agent. To investigate the safety and pharmacokinetics of bropirimine tablets and to measure IFN concentrations in patients with cancer, Phase I studies were conducted. In single dose study (0.25 to 3g) and multiple-dose study with one-day dosing (1 or 2g, every one or two hours, three times a day), bropirimine treatment was well tolerated by the patients with cancer. In multiple-dose study with consecutive days dosing (1 or 2g, every 2 hours, three times a day for 3 or 5 consecutive days), a regimen with a dose of 1g orally administered every two hours, three times a day for three consecutive days was considered to be tolerable to cancer patients. Adverse drug reactions frequently observed were generalized malaise, fever, nausea/vomiting, anorexia, headache/dull headache, and tachycardia. Abnormalities in laboratory tests frequently observed were leukemia, neutropenia, thrombocytopenia, and elevation in GOT/GPT. IFN was not induced in any patients in the single dose study. It was, however, induced in 3 of 16 cases (18.8%) in the one-day dosing study and in 6 of 7 cases (85.7%) in the consecutive days dosing study. As to clinical antitumor efficacy, a decrease in size of the tumor lesions and improvement in subjective/objective symptoms were noted in two cases in the one-day dosing study. With these findings, the regimen with the dose of 1g orally administered every two hours, three times a day for three consecutive days with a four-day drug-free interval per week was recommended for early phase II studies.

Topics: Administration, Oral; Adult; Aged; Antineoplastic Agents; Cytosine; Drug Administration Schedule; Female; Humans; Interferon Inducers; Interferons; Killer Cells, Natural; Male; Middle Aged; Neoplasms

Topics: Antineoplastic Agents; Cytosine; Drug Evaluation; Humans; Neoplasms

2-Amino-5-bromo-6-phenyl-4(3H)-pyrimidinone (ABPP) was given to 59 patients in a Phase I study. The agent was selected because it is an interferon inducer and an immunotherapeutic agent in animal tumor models. The study was conducted in two phases. In the first phase, the drug was administered as a single oral dose of 25-2,000 mg/m2. In the second part, the highest tolerated dose reached during part one was used as the initial dose in a multiple-dose scheme of treatment. Patients were treated weekly. The dose was escalated each week, starting with a dose of 2 g/m2 and escalating to 3, 4, and 5 g/m2. No cardiac, hematologic, hepatic, or renal toxicity was observed. The most common toxicity was nausea and vomiting, which occurred in 18% of the patients; others were headache (8%), abdominal pain (8%), and diarrhea (6%). No consistent induction of interferon and no major modification of host defense parameters occurred. One patient with malignant melanoma showed evidence of tumor regression. Pharmacologic studies demonstrated a significant decrease in the bioavailability of the drug as it was administered in this study. Further studies of ABPP with a preparation that has good availability are indicated to determine the potential antitumor activity of this agent or this class of agents in humans.

Topics: Adult; Aged; Cytosine; Drug Evaluation; Humans; Interferon Inducers; Interferons; Male; Melanoma; Middle Aged; Neoplasms