RESUMO
A majority of the novel orally administered, molecularly targeted anticancer therapies are weak bases that exhibit pH-dependent solubility, and suppression of gastric acidity with acid-reducing agents could impair their absorption. In addition, a majority of cancer patients frequently take acid-reducing agents to alleviate symptoms of gastroesophageal reflux disease, thereby raising the potential for a common but underappreciated drug-drug interaction (DDI) that could decrease the exposure of anticancer medication and result in subsequent failure of therapy. This article is a review of the available clinical literature describing the extent of the interaction between 15 orally administered, small-molecule targeted anticancer therapies and acid-reducing agents. The currently available clinical data suggest that the magnitude of this DDI is largest for compounds whose in vitro solubility varies over the pH range 1-4. This range represents the normal physiological gastric acidity (pH ~1) and gastric acidity while on an acid-reducing agent (pH ~4).
Assuntos
Anticarcinógenos/uso terapêutico , Refluxo Gastroesofágico/tratamento farmacológico , Neoplasias/tratamento farmacológico , Inibidores da Bomba de Prótons/uso terapêutico , Anticarcinógenos/farmacocinética , Interações Medicamentosas , Ácido Gástrico , Determinação da Acidez Gástrica , Refluxo Gastroesofágico/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Absorção Intestinal , Neoplasias/metabolismo , Inibidores da Bomba de Prótons/farmacocinética , SolubilidadeRESUMO
BACKGROUND: To evaluate the toxicity and pharmacological and biological properties of the farnesyl protein transferase (FPTase) inhibitor, tipifarnib (R115777, ZARNESTRAtrade mark) and capecitabine administered for 14 days every 3 weeks. PATIENTS AND METHODS: Patients with advanced cancers received twice daily tipifarnib (100-500 mg) and capecitabine (1000-1125 mg/m(2)) for 14 days every 3 weeks. Pharmacokinetics of tipifarnib, capecitabine and 5-fluorouracil (5-FU) were determined. Peripheral blood mononuclear cells were analyzed for farnesylation of the HDJ2 chaperone protein and FPTase activity. RESULTS: Forty-one patients received 185 courses of treatment. Diarrhea and palmar-plantar erythrodysesthesia were dose limiting at 300 mg tipifarnib/1125 mg/m(2) capecitabine b.i.d. When the capecitabine dose was fixed at 1000 mg/m(2) b.i.d., neutropenia was dose limiting at 400 and 500 mg b.i.d. of tipifarnib. Capecitabine did not affect the pharmacology of tipifarnib at 100-300 mg b.i.d., although tipifarnib significantly increased the C(max) of 5-FU at 400 mg b.i.d. HDJ2 farnesylation and FPTase activity decreased between 200 and 400 mg b.i.d. doses of tipifarnib, without a dose-response relationship. Five patients demonstrated partial remissions and 11 patients maintained prolonged stable disease. CONCLUSIONS: Tipifarnib and capecitabine are well tolerated at 300 mg/1000 mg/m(2) b.i.d., respectively, resulting in biologically relevant plasma concentrations and antitumor activity. The recommended dose for further disease-focused studies is 300 mg b.i.d. tipifarnib and 1000 mg/m(2) b.i.d. capecitabine, given for 14 days every 3 weeks.
Assuntos
Alquil e Aril Transferases/antagonistas & inibidores , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Neoplasias/tratamento farmacológico , Quinolonas/efeitos adversos , Quinolonas/farmacologia , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/farmacocinética , Antimetabólitos Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Capecitabina , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/farmacocinética , Desoxicitidina/farmacologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/sangue , Fluoruracila/farmacocinética , Fluoruracila/farmacologia , Proteínas de Choque Térmico HSP40/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prenilação de Proteína/efeitos dos fármacos , Quinolonas/administração & dosagem , Quinolonas/farmacocinéticaRESUMO
BACKGROUND: ZD6474 selectively inhibits the tyrosine kinase activity of vascular endothelial growth factor receptor and epidermal growth factor receptor. The safety, tolerability and pharmacokinetics of ZD6474 were assessed in a phase I dose-escalation study of patients with advanced solid tumors. PATIENTS AND METHODS: Adult patients with tumors refractory to standard treatments received once-daily oral ZD6474 (50-600 mg) in 28-day cycles, until disease progression or unacceptable toxicity was observed. RESULTS: Seventy-seven patients were treated at doses of 50 mg (n=9), 100 mg (n=19), 200 mg (n=8), 300 mg (n=25), 500 mg (n=8), and 600 mg (n=8). Adverse events were generally mild, and the most common dose-limiting toxicities (DLT) were diarrhea (n=4), hypertension (n=4), and rash (n=3). The incidence of most adverse events appeared to be dose-dependant. In the 500 mg/day cohort, 3/8 patients experienced DLT and this dose was therefore considered to exceed the maximum tolerated dose. Pharmacokinetic analysis confirmed that ZD6474 was suitable for once-daily oral dosing. CONCLUSIONS: Once-daily oral dosing of ZD6474 at 300 mg/day is generally well tolerated in patients with advanced solid tumors, and this dose is being investigated in phase II trials.
Assuntos
Antineoplásicos/administração & dosagem , Receptores ErbB/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Piperidinas/administração & dosagem , Quinazolinas/administração & dosagem , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacocinética , Relação Dose-Resposta a Droga , Esquema de Medicação , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacocinética , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/patologia , Piperidinas/farmacocinética , Quinazolinas/farmacocinéticaAssuntos
Inibidores da Angiogênese/uso terapêutico , Estradiol/análogos & derivados , Neoplasias/tratamento farmacológico , Compostos Orgânicos , 2-Metoxiestradiol , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Colágeno/uso terapêutico , Endostatinas , Fatores de Crescimento Endotelial/imunologia , Inibidores Enzimáticos/uso terapêutico , Estradiol/uso terapêutico , Humanos , Ácidos Hidroxâmicos/uso terapêutico , Linfocinas/imunologia , Inibidores de Metaloproteinases de Matriz , Fragmentos de Peptídeos/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Talidomida/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
Complementary and genomic clones encoding the mRNA and gene for a protein in the Syrian hamster that is highly homologous to C-reactive protein (CRP) have been isolated and studied. Coding sequence of the genomic clone is identical with that of the cDNA clone and predicts a mature protein of 206 amino acids and a 19 amino acid signal peptide. The single intron is 217 base pairs long and contains a short repetitive (GT)n motif. RNA blot analysis demonstrates that mRNA for hamster CRP is approximately 2.0 kb long, and unlike the closely related pentraxin female protein (FP), expression of this mRNA is not affected by the gender of the animal and accumulates equally in males and females during inflammation. In vivo administration of interleukin 1, interleukin 6, and tumor necrosis factor induces accumulation of hepatic CRP mRNA, and the acute-phase alterations in CRP mRNA levels arise as a result of enhanced gene transcription.
Assuntos
Proteína C-Reativa/genética , Mesocricetus/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Cricetinae , Citocinas/farmacologia , Expressão Gênica/efeitos dos fármacos , Genes , Humanos , Camundongos , Dados de Sequência Molecular , Oligonucleotídeos/química , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Coelhos , Ratos , Mapeamento por Restrição , Alinhamento de Sequência , Transcrição GênicaRESUMO
We examined the effects of synthetic human atrial natriuretic factor (human ANF 99-126) on adenylate cyclase activity, cAMP and cyclic GMP (cGMP) levels, bone resorption, collagen and DNA synthesis, and prostaglandin E2 (PGE2) production in fetal rat bone organ cultures. ANF (100 nM) inhibited PTH- and PGE2-stimulated cAMP production but had no effect on basal cAMP production in 21-day fetal rat calvaria. ANF increased cGMP levels, and this was not affected by PTH. ANF (10 nM) partially inhibited bone resorption stimulated by PGE2 but had no effect on control or PTH-stimulated resorption in 19-day fetal rat long bones. ANF had no effect on collagen and DNA synthesis or PGE2 production and did not alter responses to PTH or PGE2 in the fetal rat calvaria. Thus, ANF has no major direct effect on bone resorption or formation, but it is possible that ANF modulates the local regulatory function of PGE2 in bone.