Cytarabine Ocfosfate Research Articles

Oral cytarabine ocfosfate pharmacokinetics and assessment of leukocyte biomarkers in normal dogs.

Cytosine arabinoside (Ara-C) is a nucleoside analog prodrug utilized for immunomodulatory effects mediated by its active metabolite Ara-CTP. Optimal dosing protocols for immunomodulation in dogs have not been defined. Cytarabine ocfosfate (CO) is a lipophilic prodrug of Ara-C that can be administered PO and provides prolonged serum concentrations of Ara-C. Provide pharmacokinetic data for orally administered CO and determine accumulation and functional consequences of Ara-CTP within peripheral blood leukocytes. Three healthy female hound dogs and 1 healthy male Beagle. Prospective study. Dogs received 200 mg/m2 of CO PO q24h for 7 doses. Serum and cerebrospinal fluid (CSF) CO and Ara-C concentrations were measured by liquid chromatography-tandem mass spectroscopy (LC-MS/MS). Complete blood counts, flow cytometry, and leukocyte activation assays were done up to 21 days. Incorporation of Ara-CTP within leukocyte DNA was determined by LC-MS/MS. Maximum serum concentration (Cmax ) for Ara-C was 456.1-724.0 ng/mL (1.88-2.98 μM) and terminal half-life was 23.3 to 29.4 hours. Cerebrospinal fluid: serum Ara-C ratios ranged from 0.54 to 1.2. Peripheral blood lymphocyte concentrations remained within the reference range, but proliferation rates poststimulation were decreased at 6 days. Incorporation of Ara-CTP was not saturated and remained >25% of peak concentration at 13 days. Oral CO may produce prolonged serum Ara-C half-lives at concentrations sufficient to induce functional changes in peripheral leukocytes and is associated with prolonged retention of DNA-incorporated Ara-CTP. Application of functional and active metabolite assessment is feasible and may provide more relevant data to determine optimal dosing regimens for Ara-C-based treatments.

Persistent molecular remission of refractory acute myeloid leukemia with inv(16)(p13.1q22) in an elderly patient induced by cytarabine ocfosfate hydrate

The prognosis of relapsed acute myeloid leukemia (AML) in elderly patients is dismal, even if the AML exhibits a good prognostic karyotype, such as inv(16)(p13.1q22). We present a 72-year-old female with AML with inv(16)(p13.1q22) who suffered five episodes of relapse with temporary complete remission. Maintenance chemotherapy with oral cytarabine ocfosfate hydrate eventually produced persistent molecular complete remission of her AML that had not been induced by conventional regimens including intensive chemotherapy and low dose cytarabine therapy. The high level of tolerability to oral cytarabine ocfosfate hydrate may offer elderly patients with this type of AML a good chance for a cure.Electronic supplementary materialThe online version of this article (doi:10.1186/s13045-014-0100-6) contains supplementary material, which is available to authorized users.

Efficacy of Oral Cytarabine Ocfosfate and Etoposide in the Treatment of Elderly Patients with Higher-Risk Myelodysplastic Syndromes Compared to That in Elderly Acute Myeloid Leukemia Patients

Background: Elderly acute myeloid leukemia (AML) patients and patients with higher-risk myelodysplastic syndromes (MDS) have a much poorer prognosis than younger patients despite intensive chemotherapy. Methods: Ten patients with higher-risk MDS and 12 patients with AML over 65 years of age were enrolled into this study and received oral induction therapy with cytarabine ocfosfate and etoposide. Results: The therapy response rates were 60% in the MDS group and 41.7% in the AML group. The difference in overall survival among MDS and AML patients was not statistically significant. The difference in the median survival times of the responsive and nonresponsive groups, which included MDS and AML patients, was statistically significant (790 and 174 days, respectively). Conclusions: Based on a comparison of the data of this therapy in elderly higher-risk MDS patients versus elderly AML patients, we conclude that this therapy is well tolerated and can be cost-effective and useful for higher-risk MDS in elderly patients.

Cytarabine ocfbsfate 投与により QOL 面での改善がみられた CMMoL の1女児例

Cytarabine ocfbsfate 投与により QOL 面での改善がみられた CMMoL の1女児例

少量Ara-CとG-CSFの併用で寛解に導入し，経口Ara-Cで長期に寛解を維持しているM0の1例

少量Ara-CとG-CSFの併用で寛解に導入し，経口Ara-Cで長期に寛解を維持しているM0の1例

The value of oral cytarabine ocfosfate and etoposide in the treatment of refractory and elderly AML patients

Twenty-one acute myeloid leukemia (AML) patients were enrolled and received oral induction therapy with cytarabine ocfosfate (SPAC) and etoposide (EP). The median age was 69 years (range: 33-86). There were 11 patients with de novo AML and 10 AML cases that had evolved from myelodysplastic syndromes. Seventeen patients had abnormal karyotypes including eight complex abnormalities, various complications, and 7 of 21 had a poor performance status (PS) with Eastern Cooperative Oncology Group (ECOG) scores of 3-4. All patients completed induction therapy without severe adverse events. Seven achieved complete remission (CR), and two achieved partial remission (PR). Uni- and multivariate analyses demonstrated a positive and significant correlation between the results of therapy (CR +/- PR) and overall survival. The plasma concentrations of cytosine arabinoside (ara-C) in some cases were higher than those previously reported, indicating the accumulation of ara-C with increasing numbers of days of SPAC administration. We conclude that this therapy is well tolerated and useful for refractory and elderly AML patients.

Lower Dose of Imatinib Provides Outcomes Similar to the Standard Dose Imatinib in Japanese Patients with Early Chronic-Phase CML: The Interim Analyses of JALSG CML202 Study.

Background: The dose of imatinib 400 mg is considered to be standard for chronic-phase chronic myeloid leukemia (CML) based on the IRIS study. However, the optimal dose of imatinib is not yet settled and the response of lower dose imatinib has not been investigated. Lower dose of imatinib might be enough in Asian patients since the results of PK in IRIS study showed weak correlation between imatinib trough level and body weight. We showed the results of the interim analysis of JALSG CML202 study and analyzed the efficacy of imatinib according to the mean daily dose level.Methods: The objectives of CML202 study are to determine the efficacy of imatinib monotherapy in patients with newly diagnosed chronic-phase CML, and to test whether combining imatinib with IFN or cytarabine ocfosfate overcome the resistance of imatinib and to estimate the frequency and severity of toxicities. Primary end point of imatinib monotherapy was overall survival, and that of combination therapy was cytogenetic response after 9 months. Newly diagnosed patients with chronic phase CML will receive imatinib at a dose of 400mg daily. At 9 months, if patients don't achieve major cytogenetic response (MCR), they were randomized to the combination therapies, imatinib plus conventional IFN or imatinib plus cytarabine ocfosfate.Results: From 2002 to 2006, 489 patients were enrolled to this study. On July 2007, 36 months median follow-up data were analyzed. Only 2 patients were enrolled to the combination therapy because a majority of patients achieved good response. 13 patients underwent HSCT. The estimated cumulative rates of complete hematologic response (CHR), MCR and complete cytogenetic response (CCR) were 97%, 97% and 91%, respectively. The estimated major molecular response (MMR) rate at 24 months was 55%. The estimated survival without AP/BC progression rate at 60 months was 94%. The overall estimated survival at 60 months was 94%. 95% of low risk patients achieved CCR significantly as compared with intermediate and high-risk patients according to Sokal risk. The mean daily dose of imatinib for the first 2 years was 400mg or more in 54% patients (400mg group), 300–399mg in 27% (300mg group), 200–299mg (200mg group) in 11%, and 100–199mg in 9% (100mg group), respectively. The cumulative rate of MCR and CCR at 60 months was 99% and 97% in 400mg group, 99% and 98% in 300mg group, 92% and 85% in 200mg group, and 81% and 48% in 100mg group, respectively (p=0.003 and p<0.0001). The cumulative rate of MMR at 18 months was 33% in 400mg group, 33% in 300mg group, 27% in 200mg group and 0% in 100mg group, respectively. The estimated rate of overall survival and progression-free survival at 60 months was 97% and 97% in 400mg group, 98% and 98% in 300mg group, 92% and 92% in 200mg group, and 87% and 87% in 100mg group, respectively (p=0.0002 and p=0.0009).Conclusion: The results of interim analyses of JALSG study were almost similar to those of IRIS study. However, the mean daily dose of imatinib was lower in our study than in IRIS study. The patients received imatinib 300mg showed outcomes similar to 400mg, suggesting that imatinib 300mg might be enough for Japanese patients. The comparative studies with PK measurement will ellucidate the optimal dose of imatinib.

P-105 The value of oral cytarabine ocfosfate and etoposide in the treatment of elderly patients with high-risk myelodysplastic syndromes

P-105 The value of oral cytarabine ocfosfate and etoposide in the treatment of elderly patients with high-risk myelodysplastic syndromes

Interferon-α-2b and oral cytarabine ocfosfate for newly diagnosed chronic myeloid leukaemia

Treatment with interferon and subcutaneous cytarabine produces superior cytogenetic responses in chronic myeloid leukaemia (CML) than treatment with interferon alone, but at the expense of greater toxicity. Cytarabine ocfosfate (YNK01) is an oral precursor of cytarabine that may overcome some of the inconvenience and toxicities associated with subcutaneous cytarabine administration. We studied the efficacy and tolerability of combination therapy with interferon-alpha-2b and YNK01 in patients with newly diagnosed, untreated CML. Forty patients were treated with interferon-alpha-2b (5 MU/m2/day) plus monthly courses of YNK01 (600 mg/day for 10 days) for 1 year. The 6-month complete haematological response rate was 63% and the 1-year major cytogenetic response rate was 30%, with 10% of cytogenetic responses being complete. With a median follow-up of 57 months, the estimated 5-year overall survival was 86% (95% confidence interval 70% to 94%). Treatment tolerability was poor, with toxicity leading to discontinuation of one or both drugs in 60% of cases. The median daily dose of interferon alpha-2b was 7.75 MU and the median dose of YNK01 was 600 mg/day for each 10-day treatment cycle. Interferon-alpha-2b and YNK01 produce cytogenetic responses comparable to those achieved with interferon-alpha-2b and parenteral cytarabine, although toxicity was excessive. Alternate dosing strategies may enhance the tolerability of YNK01.

Clinical pharmacokinetics of cytarabine formulations.

Cytarabine (cytosine arabinoside, Ara-C) is an effective chemotherapeutic agent for the treatment of acute myelogenous leukaemia and lymphocytic leukaemias. As cytarabine is an S-phase-specific drug, prolonged exposure of cells to cytotoxic concentrations is critical to achieve maximum cytotoxic activity. However, the activity of cytarabine is decreased by its rapid deamination to the biologically inactive metabolite uracil arabinoside. This rapid deamination is the reason for the ongoing search for effective formulations and derivatives of cytarabine that cannot be deaminated and exhibit better pharmacokinetic parameters. Protection of cytarabine from fast degradation and elimination has been investigated by encapsulating the drug into pharmaceutically acceptable carriers. Cytarabine derivatives have shown promise in vitro and in animal models. For example, ancitabine (cyclocytidine), enocitabine and cytarabine ocfosfate have been used clinically in Japan. Cytarabine encapsulated into multivesicular liposomes has been approved in several countries for the intrathecal treatment of lymphomatous meningitis. Although many compounds have been investigated, few cytarabine derivatives are currently available for clinical use. Further research is needed to improve the efficacy of cytarabine against haematological and solid tumours.

Continuous oral cytarabine ocfosfate with interferon-alpha-2b for patients with newly diagnosed chronic myeloid leukaemia: a pilot study.

Recombinant(R) interferon alpha (r-IFN-alpha) has been shown to be an effective drug for chronic myeloid leukaemia (CML). However, higher response rates can be achieved using cytarabine along with r-IFN-alpha. YNK01 is a derivative of cytosine arabinoside for oral administration. So far, the only published experience with continuous YNK01 was in advanced CML (10 cases). We have performed a pilot study to evaluate the efficacy and toxicity of the combined therapy r-IFN-alpha and daily oral YNK01 in patients with newly diagnosed Ph+ CML. Ten previously untreated patients were included in the study. Among those patients evaluable for cytogenetic response, 87% (seven out of eight) reached a major cytogenetic response with four reaching complete cytogenetic response (50%). The most significant side-effects were gastrointestinal. Macrocytic anaemia was observed in three patients. In conclusion, continuous oral administration of YNK01 in combination with IFN-alpha is safe and can result in high-cytogenetic response rates.

Long-term follow-up of the clinical efficacy of chemotherapy for acute myeloid leukemia at a single institute.

A retrospective study was performed on 125 patients with de-novo acute myeloid leukemia (AML) who had received first remission induction therapy at Fukui Medical University Hospital in the 16 years between 1983 and 1998. For remission induction therapies, patients in the 1980s received mainly behenoylcytarabine (BHAC), 6-mercaptopurine (6-MP), and prednisolone (PSL), plus aclarubicin (ACR) or daunorubicin (DNR). Patients in the 1990s received mainly BHAC, 6-MP, and etoposide (VP-16) plus DNR or mitoxantrone (MIT) or idarubicin (IDA). Patients with hypoplastic bone marrow received low-dose cytarabine (Ara-C) therapy or cytarabine ocfosfate (SPAC). Since 1992, patients with French-American-British disease classification of M3 have received all-trans retinoic acid (ATRA) (+/-chemotherapy). In the 1990s, more intensified postremission therapy was performed compared with that done in the 1980s. The complete remission (CR) rate of all patients was 58%. Predicted 6-year overall survival (OS) and disease-free survival (DFS) rates in the CR patients were 22% and 28%, respectively. Multivariate analysis showed age and leukocyte counts as significant prognostic factors regarding CR, OS, and DFS rates. The CR and OS rates in the 1990s were improved significantly from those in the 1980s, at 69% versus 48% (P = 0.016), and 32% versus 15% (P = 0.0014), respectively. The early death rate, within 30 days, was decreased from 26% in the 1980s to 9% in the 1990s (P = 0.013). This decrease was thought to be the main cause of the high CR rate in the 1990s. However, DFS was not significantly improved. It is necessary to establish more effective postremission therapies in order to reduce the relapse rate and improve the prognosis.

Treatment of patients with advanced chronic myelogenous leukemia with interferon-alpha-2b and continuous oral cytarabine ocfosfate (YNK01):: a pilot study

The efficacy of continuous oral cytarabine ocfosfate (YNK01) (300 mg/day) in combination with interferon alpha (IFNα, 5×10 6 IU/day) was evaluated in patients with advanced chronic myelogenous leukemia, who previously failed to respond to IFNα-based therapies. Dose escalations up to 900 mg YNK01 were allowed in patients who failed to respond. In view of our results, four patients developed a complete hematological response after YNK01 was started. Among those who initially responded to YNK01, one complete cytogenetic response was achieved 18 months later. Although the data are preliminary, this is the first study showing that continuous administration of YNK01 along with IFNα is effective in patients with advanced chronic myelogenous leukemia.

A Pharmacokinetic Study of the Value of Oral Cytarabine Ocfosfate in the Treatment of Hematological Malignancies

A Pharmacokinetic Study of the Value of Oral Cytarabine Ocfosfate in the Treatment of Hematological Malignancies

Treatment of acute myeloid leukemia and myelodysplastic syndrome with orally administered cytarabine ocfosfate and granulocyte colony-stimulating factor.

Cytarabine ocfosfate (SPAC) was administered orally to 19 patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). SPAC was administered at doses of 200-300 mg/day for more than 14 days with granulocyte colony-stimulating factor (G-CSF). Four of the 12 patients with AML and 1 of the 7 patients with MDS achieved complete remission (CR) after one cycle of SPAC treatment. Especially, 3 of the 6 patients with newly diagnosed AML achieved CR. Major side effects of SPAC were myelosuppression and tolerable gastrointestinal disorders. The treatment with SPAC is a therapeutic option in elderly patients or patients with organ failure.

Characteristic antitumor activity of cytarabine ocfosfate against human colorectal adenocarcinoma xenografts in nude mice

The antitumor activity of cytarabine ocfosfate (SPAC) was tested against human colorectal, gastric and lung adenocarcinoma xenografts in nude mice in comparison with the activities of various antitumor drugs used clinically. SPAC showed higher therapeutic efficacy against human colorectal adenocarcinoma xenografts than against human gastric and lung adenocarcinoma xenografts. SPAC was effective against three of four human colorectal adenocarcinoma xenografts, with efficacy higher than that of 1-beta-D-arabinofuranosylcytosine, fluorouracil, cisplatin, doxorubicin, pirarubicin and vindesine sulfate, but lower than that of mitomycin C and cyclophosphamide. These results indicate that SPAC may be useful for induction and/or postoperative chemotherapy against colorectal adenocarcinomas.

Plasma concentration of cytosine arabinoside (Ara-C) in the elderly patients with hematological malignancy treated by Ara-C or cytarabine ocfosfate (SPAC)

Plasma concentration of cytosine arabinoside (Ara-C) was determined in elderly patients with myelodysplastic syndromes or acute myelocytic leukemia who were treated with subcutaneous injection of Ara-C (Ara-C s.c.; 10 mg/m2/12 hr, 14-21 days), continuous drip infusion of Ara-C (Ara-C d.i.v.; 20 mg/m2/day, 24 hr 14 days) and/or oral administration of cytarabine ocfosfate (SPAC) (SPAC p.o.; 100 mg-300 mg/body/day, 14 days) by radioimmunoassay. In the Ara-C s.c. patients, the peak plasma level (Cmax) of Ara-C was 103 ng/ml and the time to reach Cmax was 15 min. The elimination half-like (t1/2) was 25 min and no accumulation was detected after 14 days of consecutive Ara-C s.c. administrations. In the SPAC p.o. patients, Cmax of Ara-C was 3-8 ng/ml and it took 3-5 days to reach Cmax. The plasma concentration level of Ara-C remains almost at the Cmax level during the SPAC p.o. administration and it remained higher than 0.32 ng/ml for as long as 15 days after the end of administration. In a Ara-C d.i.v. patient, plasma level of Ara-C was detected 4-7 ng/ml during the administration (day 7 through day 14). In all patients bone marrow suppression was observed after chemotherapy regardless of regimen, and there was no significant difference between nadir peripheral cell blood counts of Ara-C s.c. patients and SPAC p.o. patients.

Cytarabine ocfosfateの内服治療のみで完全寛解に到達した高齢者のhypoplastic leukemia

Cytarabine ocfosfateの内服治療のみで完全寛解に到達した高齢者のhypoplastic leukemia

Cytarabine Ocfosfate Upregulates the Effect of Granulocyte Colony-stimulating Factor in Myelodysplastic Syndrome with Monosomy 7

Cytarabine Ocfosfate Upregulates the Effect of Granulocyte Colony-stimulating Factor in Myelodysplastic Syndrome with Monosomy 7