piperidines and Myelodysplastic-Syndromes

The farnesyltransferase inhibitors (FTIs) are in active clinical development in a variety of human malignancies. The most promising activity to date has been demonstrated in patients with hematologic malignancies, in particular acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). In patients with MDS, two nonpeptidomimetic agents, tipifarnib (Zarnestra, Johnson & Johnson, New Brunswick, NJ) and lonafarnib (Sarasar, Schering-Plough, Kenilworth, NJ) have been the most extensively studied. In both phase I and phase II trials, tipifarnib has demonstrated significant efficacy, with overall response rates of 30% and complete remissions in about 15%. Dose-limiting adverse effects have been primarily myelosuppression, although fatigue, neurotoxicity, and occasional renal dysfunction have required dose reductions. Lonafarnib in patients with MDS has also resulted in clinical responses in approximately 30%, including significant improvements in platelet counts. Lonafarnib has been associated primarily with diarrhea and other gastrointestinal toxicity, anorexia, and nausea, which has limited its efficacy. Clinical response correlation with documentation of inhibition of farnesyltransferase and/or evidence of decreased farnesylation of downstream protein targets has not been demonstrated with either agent. In addition, the presence of an activating Ras mutation has not predicted response to therapy with FTIs in MDS and AML. Despite this lack of evidence, significant clinical efficacy of the FTIs has been observed in MDS, on a par with the efficacy of currently available chemotherapeutic agents, leading to further development of this new class of drugs in MDS and AML.

Topics: Adult; Aged; Antineoplastic Agents; Bone Marrow Diseases; Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Disease Progression; Farnesyltranstransferase; Gastrointestinal Diseases; Genes, ras; Hematologic Neoplasms; Humans; Middle Aged; Myelodysplastic Syndromes; Piperidines; Prenylation; Protein Processing, Post-Translational; Pyridines; Quinolones; Treatment Outcome

The farnesyltransferase inhibitors (FTIs) are in active clinical development in a variety of human malignancies. The most promising activity to date has been demonstrated in patients with hematological malignancies, in particular acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). In patients with MDS, two non-peptidomimetic agents, tipifarnib (Zarnestra, Johnson & Johnson, New Brunswick, NJ) and lonafarnib (Sarasar, Schering-Plough, Kenilworth, NJ) have been the most extensively studied. In both phase I and phase II trials, tipifarnib has demonstrated significant efficacy with overall response rates of 30%, with complete remissions in about 15%. Dose-limiting side effects have been primarily myelosuppression, although fatigue, neurotoxicity, and occasional renal dysfunction have required dose reductions. Lonafarnib in patients with MDS has also resulted in clinical responses in approximately 30%, including significant improvements in platelet counts. Lonafarnib has been associated with primarily diarrhea and other gastrointestinal toxicity, anorexia, and nausea, which has limited its efficacy. Clinical response correlation with documentation of inhibition of farnesyltransferase and/or evidence of decreased farnesylation of downstream protein targets has not been demonstrated with either agent. In addition, the presence of an activating Ras mutation has not predicted response to therapy with FTIs in MDS and AML. Despite this, significant clinical efficacy of the FTIs in MDS, on par with that of currently available chemotherapeutic agents, has been observed, leading to further development of this new class of drugs in MDS and AML.

Topics: Acute Disease; Aged; Alkyl and Aryl Transferases; Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Disease Progression; Enzyme Inhibitors; Farnesyltranstransferase; Genes, ras; Hematologic Neoplasms; Humans; Leukemia, Myeloid; Middle Aged; Myelodysplastic Syndromes; Piperidines; Protein Prenylation; Protein Processing, Post-Translational; Proto-Oncogene Proteins p21(ras); Pyridines; Quinolones; Remission Induction; Signal Transduction; Treatment Outcome

The treatment of older, unfit patients with acute myeloid leukemia (AML) is challenging. Based on preclinical data of Bruton tyrosine kinase expression/phosphorylation and ibrutinib cytotoxicity in AML blasts, we conducted a randomized phase 2 multicenter study to assess the tolerability and efficacy of the addition of ibrutinib to 10-day decitabine in unfit (ie, Hematopoietic Cell Transplantation Comorbidity Index ≥3) AML patients and higher risk myelodysplasia patients (HOVON135/SAKK30/15 trial). In total, 144 eligible patients were randomly (1:1) assigned to either 10-day decitabine combined with ibrutinib (560 mg; sequentially given, starting the day after the last dose of decitabine) (n = 72) or to 10-day decitabine (n = 72). The addition of ibrutinib was well tolerated, and the number of adverse events was comparable for both arms. In the decitabine plus ibrutinib arm, 41% reached complete remission/complete remission with incomplete hematologic recovery (CR/CRi), the median overall survival (OS) was 11 months, and 2-year OS was 27%; these findings compared with 50% CR/CRi, median OS of 11.5 months, and 2-year OS of 21% for the decitabine group (not significant). Extensive molecular profiling at diagnosis revealed that patients with STAG2, IDH2, and ASXL1 mutations had significantly lower CR/CRi rates, whereas patients with mutations in TP53 had significantly higher CR/CRi rates. Furthermore, multicolor flow cytometry revealed that after 3 cycles of treatment, 28 (49%) of 57 patients with available bone marrow samples had no measurable residual disease. In this limited number of cases, measurable residual disease revealed no apparent impact on event-free survival and OS. In conclusion, the addition of ibrutinib does not improve the therapeutic efficacy of decitabine. This trial was registered at the Netherlands Trial Register (NL5751 [NTR6017]) and has EudraCT number 2015-002855-85.

Topics: Adenine; Decitabine; Humans; Leukemia, Myeloid, Acute; Myelodysplastic Syndromes; Netherlands; Piperidines

Lonafarnib is an orally bio-available farnesyltransferase inhibitor that prevents farnesylation of specific target proteins including Ras. In a multicenter study, 67 patients with advanced myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia (CMML) were treated with a continuous oral dose of 200-300 mg of lonafarnib and were evaluated for hematologic, pathologic and pharmacodynamic response. The median age of patients was 70 years (range 44-86). There were 32 patients with MDS (RAEB-20 and RAEB-t-12) and 35 with CMML. Overall 16 (24%) of the patients responded with two patients achieving a complete remission and one a partial response. Responses were seen in 6/32 and 10/35 patients with MDS and CMML, respectively. Of the 19 patients who were platelet transfusion-dependent prior to treatment, 5 (26%) became transfusion-free for a median duration of 185 days. A decrease in the farnesylation of the HDJ-2 protein measured in patient-derived cells was observed in the majority of patients during treatment with lonafarnib, but no clear correlation between changes in farnesylation and clinical effect could be made. Gastrointestinal toxicity was significant with 19% of patients discontinuing therapy due to diarrhea, nausea and/or anorexia. Lonafarnib has demonstrable activity in patients with advanced MDS and CMML.

Topics: Adult; Aged; Aged, 80 and over; Drug Monitoring; Enzyme Inhibitors; Farnesyltranstransferase; Gastrointestinal Diseases; Humans; Leukemia, Myelomonocytic, Chronic; Maximum Tolerated Dose; Middle Aged; Myelodysplastic Syndromes; Piperidines; Pyridines; Remission Induction; Treatment Outcome

Although an activating mutation of Ras is commonly observed in myelodysplastic syndrome (MDS), the role of Ras in the natural history of MDS remains largely unknown. We prospectively studied efficiency and tolerance of lonafarnib, a compound able to inhibit Ras signalling pathway through an inhibition of farnesyl transferase, in patients with MDS or secondary acute myeloid leukaemia (sAML). Lonafarnib was administered orally at a dose of 200 mg twice daily for three courses of 4 weeks (separated by 1 to 4 weeks without treatment). Sixteen patients were included: FAB/RAEB (n = 10), RAEB-T (n = 2), sAML (n = 2) and chronic myelomonocytic leukaemia (CMML; n = 2); WHO/RAEB-1 (n = 4), RAEB-2 (n = 5), AML (n = 5), CMML (n = 2). Median age was 70 (53-77) years. The karyotype was complex or intermediate in 11 patients, and the International Prognostic Scoring Systems (IPSS) risk groups were low in two patients, INT-1 in one patient, INT-2 in four patients and high in six patients (unknown or not applicable in three patients). Among the 14 patients tested, five had Ras mutations in codons 12, 13 or 61 of N-Ras, K-Ras or H-Ras. One patient was excluded of the analysis for protocol violation, and 15 patients were assessable for tolerance. Gastrointestinal toxicities (diarrhoea, nausea and anorexia) and myelosuppression were the major side effects. Other toxicities included infections, fatigue, increase of liver enzymes, arrhythmia and skin rash. One patient died of infection, and the treatment was stopped in one other who developed atrial fibrillation. Doses were reduced in all but one patient treated with more than one course of farnesyl transferase inhibitor. Responses were assessable in 12 patients. A partial response in one sAML patient and a very transient decrease of blast cell count with normalisation of karyotype in one MDS patient were observed. No relation between improvement of marrow parameters and detected Ras mutations was observed. Lonafarnib alone, administered following our schedule, has shown limited activity in patients with MDS or secondary AML. Gastrointestinal and haematological toxicities appear the limiting toxicity in this population of patients.

Topics: Aged; Farnesyltranstransferase; Female; Gastrointestinal Diseases; Genes, ras; Humans; Leukemia, Myeloid, Acute; Male; Middle Aged; Myelodysplastic Syndromes; Piperidines; Pyridines

Poly(ADP-ribose) polymerase (PARP) proteins are used by cells in several DNA repair processes. PARP inhibition can result in preferential death of cancer cells when another mechanism for repairing DNA is defective. Two PARP inhibitors, olaparib and rucaparib, have been approved by the US Food and Drug Administration (FDA) for the treatment of recurrent, BRCA-associated ovarian cancer. More recently, these two and a third PARP inhibitor, niraparib, were approved by the FDA as maintenance therapy following platinum-based chemotherapy for recurrent ovarian cancer. This has caused a paradigm shift in disease management and a challenge for clinicians, who must decide how best to use these agents in individualized treatment. The oral formulation is attractive to patients, but adverse effects such as nausea and fatigue can impact quality of life. As clinicians become comfortable selecting PARP inhibitors and managing associated toxicities, future steps will be to investigate how to safely administer them in combination with other therapies.

Topics: Anemia; Creatinine; Drug Administration Schedule; Drug Interactions; Exanthema; Fatigue; Female; Genes, BRCA1; Genes, BRCA2; Heart Rate; Humans; Hypertension; Indazoles; Leukopenia; Mutation; Myelodysplastic Syndromes; Nasopharyngitis; Nausea; Ovarian Neoplasms; Piperidines; Pneumonia; Poly(ADP-ribose) Polymerase Inhibitors; Thrombocytopenia; Transaminases; Vomiting

Grover's disease (GD), or transient acantholytic dermatosis, is a persistent recurrent dermatosis that usually occurs in men older than 50 years. Rare cases of GD and hematologic malignancy in the same cutaneous biopsy specimen have been reported. We report a case of GD in association with leukemia cutis. A 72-year-old man with a history of myelodysplastic syndrome presented with numerous pruritic papules on the torso, which were clinically diagnosed as GD. A skin biopsy revealed foci of suprabasal acantholysis and dyskeratosis consistent with GD and dense aggregates of mononuclear atypical cells in the superficial dermis consistent with leukemia cutis. Direct immunofluorescence was negative. This case illustrates the need to consider a diagnostic skin biopsy in any patient who presents with classic clinical findings of GD if there is any indication that the patient may be at higher risk for a hematologic malignancy.

Topics: Acantholysis; Aged; Antineoplastic Agents; Biopsy; Dermis; Fatal Outcome; Flavonoids; Humans; Hydroxamic Acids; Ichthyosis; Leukemia; Leukemic Infiltration; Male; Myelodysplastic Syndromes; Piperidines; Salvage Therapy; Skin Neoplasms; Vorinostat

Farnesyltransferase inhibitors were initially developed as Ras inhibitors as they inhibit the prenylation necessary for Ras activation. It is clear now that their mechanism of action is more complex and probably involves other proteins unrelated to Ras. At least 3 drugs within this family have been investigated in acute myeloid leukemia, myelodysplastic syndromes, and other leukemias. These are tipifarnib (R115777, Zarnestra), lonafarnib (SCH66336, Sarasar), and BMS-214662. The first 2 are administered orally, whereas BMS-214662 is given intravenously. These drugs are at different stages of development, and design of treatment schedules and methodology of the available studies are very different. Although most of the information is still preliminary, these agents have demonstrated clear evidence of clinical activity in these diseases and very favorable toxicity profiles. Several studies are still ongoing to better define the efficacy of these agents in the treatment of leukemias, as well as to determine the best schedules, the role of combination with other agents, and the role of these agents in different settings, such as the management of minimal residual disease. It is very possible that these agents will soon find their way to the ranks of established agents for the management of myeloid malignancies

Topics: Alkyl and Aryl Transferases; Antineoplastic Agents; Benzodiazepines; Clinical Trials as Topic; Farnesyltranstransferase; Humans; Imidazoles; Leukemia, Myeloid, Acute; Myelodysplastic Syndromes; Piperidines; Pyridines; Quinolones