PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “CYCLOPHOSPHAMIDE”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources

Immunomodulating effects of synchronised plasmapheresis and intravenous bolus cyclophosphamide in systemic lupus erythematosus.

Recent studies have suggested that synchronised plasmapheresis and intravenous pulse cyclophosphamide therapy reduce disease activity in SLE patients. The aim of the present study was to examine the immunomodulating effects of this therapy and compare it with changes seen with cyclophosphamide alone. Four patients with active SLE were studied. Two were treated with synchronised therapy and two received cyclophosphamide only for up to 26 weeks. Disease activity was measured by the SLE disease activity index (SLEDAI). Immunological studies were performed immediately prior to each treatment. Patients in both treatment groups improved as reflected by a fall in mean SLEDAI scores: synchronised therapy 33.5 to 11; cyclophosphamide only 13.5 to 4.5. Following synchonised therapy only there was a prompt and sustained increase in the mean percentage of CD8+ cells (20.8 to 54.8) which resulted in a fall in the CD4:CD8 ratio (1.95 to 0.62). With both treatment modalities there was a fall in the proportion of CD20+ cells (B lymphocytes) (synchronised therapy 10.5 to 3.2; cyclophosphamide only 5.6 to 2.2). However, only synchronised therapy resulted in a fall in the in vitro production of immunoglobulins which was unchanged or increased following cyclophosphamide alone. These results suggest that although both treatment modalities are efficacious in the treatment of active SLE they produce different immunomodulatory effects. Thus, both therapies reduce the number of circulating B lymphocytes whereas synchronised therapy also modifies cellular immunity by promoting the emergence of a phenotypic suppressor T lymphocyte population.

Adjuvants, Immunologic↗

Cyclophosphamide for the treatment of systemic lupus erythematosus.

Aggressive immunosuppressive therapy with cyclophosphamide has improved the outcome of major organ disease in lupus patients. Controlled trials have shown that pulse cyclophosphamide is the treatment of choice for patients with moderate to severe proliferative nephritis. Long-term follow-up of patients participating in these controlled trials suggests that combining pulse cyclophoshamide with pulse methylprednisolone increases efficacy but not toxicity. Retrospective case series have also shown that pulse cyclophosphamide therapy may be effective for the management of severe or refractory to standard therapy neuropsychiatric, pulmonary, cardiovascular and hematologic disease. Pulse cyclophosphamide is associated with an increased risk for herpes zoster infections in the short term and with sustained amenorrhea in the long-term. Recent studies have also drawn attention to the lack of response (or incomplete response) and flare of lupus after an initial response. In an effort to circumvent these limitations, current investigations explore the therapeutic potential of high-dose, immunoablative cyclophosphamide therapy or low-dose cyclophosphamide in combination with nucleoside analogs or biologic response modifiers.

Cyclophosphamide↗

Cyclophosphamide: new approaches for systemic lupus erythematosus.

Cyclophosphamide remains the 'gold standard' treatment for severe organ threatening systemic lupus erythematosus (SLE), especially renal and central nervous system lupus. Intravenous and oral cyclophosphamide have been compared, retrospectively, with similar two year remission rates of 73% and 90%. In a meta-analysis, intravenous cyclophosphamide with oral prednisone is more effective than oral prednisone alone. The efficacy of cyclophosphamide in lupus nephritis has been proven in multiple clinical trials, but efficacy has to be balanced with toxicity, including infection, gonadal failure, and malignancy. Although the continued use ofcyclophosphamide for renal lupus has been challenged by a recent trial of mycophenolate mofetil, and may be challenged in the future by planned trials of biologics, it continues to be widely used. This review will touch on the traditional intravenous 'pulse' cyclophosphamide regimen, consider its toxicity, and contrast it with newer approaches to cyclophosphamide.

Cyclophosphamide↗

Ovarian failure in systemic lupus erythematosus patients treated with pulsed intravenous cyclophosphamide.

Pulsed intravenous cyclophosphamide is considered as standard therapy for lupus nephritis and several other severe manifestations of systemic lupus erythematosus (SLE). While the response rate to intravenous cyclophosphamide is substantial, concern has arisen about its toxicity. In addition to increased susceptibility to infection, bone marrow suppression, alopecia, hemorrhagic cystitis and malignancy, ovarian failure is an important side effect associated with the use of cyclophosphamide. Prior research on cyclophosphamide-treated women has consistently demonstrated that the risk of sustained amenorrhea depends on the age of the patient and the cumulative dose received. Sustained amenorrhea is difficult to avoid in women 32 years or older, even with very short intravenous cyclophosphamide courses. Younger women seem to have a substantially lower incidence of ovarian failure, but this side effect may be far more problematic for these patients. In these young women the risk may be modulated by the prior SLE disease duration, the presence of anti-U1RNP antibodies and anti-Ro antibodies. Co-treatment with gonadotropin-releasing hormone agonists may preseserve the future fertility and ovarian function in young women. Ovarian banking before administration of cyclophosphamide should be considered in selected patients.

Alkylating Agents↗

Weekly cisplatin given for 2 months versus cisplatin plus cyclophosphamide given for 5 months after cytoreductive surgery for advanced ovarian cancer.

PURPOSE: To compare the efficacy of a treatment with cisplatin plus cyclophosphamide given for 5 months and a short treatment with cisplatin alone in advanced ovarian cancer, we conducted a multicenter randomized clinical trial. PATIENTS AND METHODS: Eligibility criteria were as follows: first diagnosis of histologically confirmed invasive epithelial ovarian cancer of International Federation of Gynecology and Obstetric (FIGO) stage III-IV, age younger than 75 years, and Eastern Cooperative Oncology Group (ECOG) performance status 0, 1, or 2. Within 28 days of cytoreductive surgery, eligible women were randomly assigned treatment with weekly cisplatin 50 mg/m2 for nine courses or cisplatin 75 mg/m2 plus cyclophosphamide 750 mg/m2 every 21 days for six courses. RESULTS: A total of 607 women were entered onto the study. There was no difference in the response to treatment. Pathologic complete response (CR) was documented in 63 of the weekly cisplatin cases and 70 of the cisplatin plus cyclophosphamide group (chi 1(2) = 1.43; P = .23). The median follow-up time was 3 years. There were 151 and 148 deaths in the weekly cisplatin and cyclophosphamide plus cisplatin arms, respectively. Survival curves were similar in the two groups, with a 3-year percent survival estimate of 44.1 (SE = 3.4) in the weekly cisplatin and 44.6 (SE = 3.4) in the cisplatin plus cyclophosphamide group (log-rank test chi 1(2) = 0.004; P = .96). CONCLUSION: This study found that 2-month monochemotherapy treatment with cisplatin was as effective as 5-month polychemotherapy including cisplatin at a similar doses but different dose-intensity plus cyclophosphamide.

Adult↗

Results of the fludarabine and cyclophosphamide combination regimen in chronic lymphocytic leukemia.

PURPOSE: To assess the efficacy of combination therapy with fludarabine and cyclophosphamide in patients with chronic lymphocytic leukemia (CLL) based on data suggesting in vitro synergistic activity of the two agents. PATIENTS AND METHODS: A total of 128 patients with CLL were treated with fludarabine 30 mg/m(2) intravenously daily for 3 days and cyclophosphamide at either 500 mg/m(2) daily for 3 days (n = 11), 350 mg/m(2)/d for 3 days (n = 26), or 300 mg/m(2) daily for 3 days (n = 91). The cyclophosphamide dose was decreased because of myelosuppression in the early part of the study. Patients were divided into four groups based on the expectation for response to single-agent fludarabine, including previously untreated patients, patients previously treated with alkylating agents, patients successfully treated with alkylating agents and fludarabine but relapsing, and patients refractory to fludarabine with or without alkylating agents. RESULTS: Fludarabine and cyclophosphamide produced > or = 80% response rates in all patients not refractory to fludarabine at the start of therapy as well as a 38% response rate in patients who were refractory to fludarabine. The complete remission (CR) rate was 35% in previously untreated patients, which was not significantly different from the CR rate in historical control patients treated with single-agent fludarabine. However, residual disease assessed by flow cytometry occurred in only 8% of previously untreated patients achieving CR, and median time to progression has not been reached after a median follow-up of 41 months. The main complication of therapy was related to myelosuppression and infection. Neutropenia to less than 500 x 10(9)/L was noted in 48% of patients who received cyclophosphamide 300 mg/m(2). Pneumonia or sepsis occurred in 25% of patients, and fever of unknown origin occurred in another 25%. Pneumonia or sepsis were significantly more frequent in patients who were refractory to fludarabine at the start of combination chemotherapy. CONCLUSION: Fludarabine and cyclophosphamide seem to have a significant advantage over single-agent fludarabine in the salvage setting. Although the CR rate was not increased in previously untreated patients, residual disease detected by flow cytometry was rare and remission durations seemed to be prolonged in this subset. Myelosuppression and infection remain the most significant complications of therapy in CLL.

Adult↗

Randomized phase II trial of letrozole and letrozole plus low-dose metronomic oral cyclophosphamide as primary systemic treatment in elderly breast cancer patients.

PURPOSE: To investigate the activity of letrozole plus/minus oral metronomic cyclophosphamide as primary systemic treatment (PST) in elderly breast cancer patients. METHODS: One hundred fourteen consecutive elderly women with T2-4 N0-1 and estrogen receptor-positive breast cancer were randomly assigned to primary letrozole therapy (2.5 mg daily for 6 months) or a combination of letrozole plus oral cyclophosphamide (50 mg/daily for 6 months) in an open-labeled, randomized phase II trial. Tumor response was assessed clinically, and tumor Ki67 index and vascular endothelial growth factor (VEGF) -A levels were measured before and after treatment. RESULTS: Overall response rate was 71.9% (95% CI, 60.0 to 83.8) in the 57 patients randomly assigned to receive primary letrozole and 87.7% (95% CI, 78.6 to 96.2) in the 57 patients randomly assigned to receive letrozole plus cyclophosphamide. The difference in activity between treatment arms was predominantly confined to patients with ductal histology. There was a significantly greater suppression of Ki67 and VEGF-A expression in the letrozole/cyclophosphamide-treated group than in the letrozole-treated group, leading to lower Ki67 and VEGF expression at post-treatment residual histology (P = .03 and P = .002, respectively). CONCLUSION: Both letrozole and letrozole plus cyclophosphamide treatments appeared active as PST in elderly breast cancer patients. Metronomic scheduling of cyclophosphamide may have an antiangiogenic effect and the combination of letrozole plus cyclophosphamide warrants testing in a randomized phase III trial.

Aged↗

Risk of acute myeloid leukemia and myelodysplastic syndrome in trials of adjuvant epirubicin for early breast cancer: correlation with doses of epirubicin and cyclophosphamide.

PURPOSE: We reviewed follow-up of patients treated in 19 randomized trials of adjuvant epirubicin in early breast cancer to determine incidence, risk, and risk factors for subsequent acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). PATIENTS AND METHODS: The patients (N = 9,796) were observed from the start of adjuvant treatment (53,080 patient-years). Cases of AML or MDS (AML/MDS) were reported, with disease characteristics. Incidence and cumulative risk were compared for possible risk factors, for assigned regimens, and for administered cumulative doses of epirubicin and cyclophosphamide. RESULTS: In 7,110 patients treated with epirubicin-containing regimens (92% of whom also received cyclophosphamide), 8-year cumulative probability of AML/MDS was 0.55% (95% CI, 0.33% to 0.78%). The risk of developing AML/MDS increased in relation to planned epirubicin dose per cycle, planned epirubicin dose-intensity, and administered cumulative doses of epirubicin and cyclophosphamide. Patients with administered cumulative doses of both epirubicin and cyclophosphamide not exceeding those used in standard regimens (</= 720 mg/m(2) and </= 6,300 mg/m(2), respectively) had an 8-year cumulative probability of developing AML/MDS of 0.37% (95% CI, 0.13% to 0.61%) compared with 4.97% (95% CI, 2.06% to 7.87%) for patients administered higher cumulative doses of both epirubicin and cyclophosphamide. CONCLUSION: Patients treated with standard cumulative doses of adjuvant epirubicin (</= 720 mg/m(2)) and cyclophosphamide (</= 6,300 mg/m(2)) for early breast cancer have a lower probability of secondary leukemia than patients treated with higher cumulative doses. Increased risk of secondary leukemia must be considered when assessing the potential benefit to risk ratio of higher than standard doses.

Adult↗

Pulmonary fibrosis induced by cyclophosphamide.

OBJECTIVE: To report a case of pulmonary fibrosis resulting from use of cyclophosphamide as chemotherapy to treat a patient with breast cancer. CASE SUMMARY: We describe the case of a 52-year-old woman with breast cancer who developed pulmonary fibrosis after four cycles of chemotherapy that included cyclophosphamide. Pulmonary function tests revealed the presence of a severe ventilatory restriction. The open lung biopsy revealed pulmonary fibrosis with vascular sclerosis and signs of pulmonary hypertension. DISCUSSION: Cyclophosphamide is an alkylating agent that has been associated with interstitial pneumonia and pulmonary fibrosis. The frequency of these unwanted effects is <1%. The clinical picture consists of the progressive appearance of dyspnea and a non-productive cough that progresses to severe pulmonary insufficiency. The risk factors described for these complications have been the use of chemotherapy regimens that include other drugs with known pulmonary toxicities, the cumulative total dose, the addition of radiotherapy, and the use of high doses of cyclophosphamide. CONCLUSIONS: Even though the frequency of pulmonary fibrosis in patients treated with cyclophosphamide-based chemotherapy regimens is low, the presence of dyspnea and an interstitial pattern in a patient makes it necessary to consider that possible drug toxicity. The open lung biopsy is the most accurate diagnostic technique for these cases. The discontinuation of cyclophosphamide and treatment with corticosteroids is usually followed by clinical recovery in approximately 50% of patients and, in some cases, reversal of the lung injury.

Antineoplastic Agents, Alkylating↗

Optimisation of cyclophosphamide therapy in systemic vasculitis.

There is no doubt that the prognosis for systemic vasculitides has been considerably improved by the use of immunosuppressive agents, chiefly cyclophosphamide. Increasingly, we are becoming aware of the enormous burden of chronic 'grumbling' disease, the high incidence of relapse and the longer term effects of toxic therapy in these patients. The general approach is more intense therapy (with intermittent high dose 'pulses' or lower dose continuous cyclophosphamide) in the initial phase of therapy to induce remission, followed by a less toxic therapy in the maintenance phase (either longer intervals between pulses or a switch to a less toxic drug, such as azathioprine). The pathogenetic mechanisms in vasculitis, which are becoming more precisely defined, are diverse, but cyclophosphamide remains the drug of choice. A number of different cyclophosphamide regimens are in use, which reflects the current dilemma of trying to balance effectiveness with toxicity in diseases where the quality of long term survival remains unsatisfactory. Evidence from controlled trials does not support major differences in immediate outcome between different regimens of cyclophosphamide. Future studies need to address the use of agents designed to interfere precisely with the underlying pathogenetic mechanisms. Alternative approaches should also be considered, for example the use of sublethal doses of cyclophosphamide, with autologous bone marrow rescue, which may achieve long lasting remission or even cure.

Controlled Clinical Trials as Topic↗

Cyclophosphamide toxicity. Characterising and avoiding the problem.

Cyclophosphamide, an orally active alkylating agent, is widely used to treat a variety of malignant and nonmalignant disorders. Although it has some tumour selectivity, it also possesses a wide spectrum of toxicities. The requirement of metabolic activation before cyclophosphamide exerts either its therapeutic or toxic effects is well established, but has not led to effective counter-measures. Clinically, damage to the bladder (haemorrhagic cystitis), immunosuppression (when not desired) and alopecia are the most significant toxicities associated with cyclophosphamide. Cardiotoxicity is also a possibility when very high doses are given. Preventing these toxicities has focused on modifications of the treatment regimens and, in the case of haemorrhagic cystitis, the administration of a drug which is excreted in the urine where it inactivates the bladder-toxic species. As treatment regimens for cancer become more effective in prolonging a patient's life, and as cyclophosphamide receives increasing use for nonmalignant disorders, the potential for cyclophosphamide-induced cancers, particularly in the bladder, must be recognised. Although the toxicities associated with cyclophosphamide are serious, this agent remains a highly effective drug in many situations. Research on the pathways which play an important role in activating this drug may improve our ability to target particular diseases and decrease unwanted side effects.

Abnormalities, Drug-Induced↗

Effect of phenobarbital on cyclophosphamide metabolism in rats.

1. The pharmacokinetics of cyclophosphamide and its alkylating metabolites have been studied in rats whose liver microsomal enzymes had been induced by phenobarbital pre-treatment. 2. Serum levels of cyclophosphamide were determined using a new g.l.c. method. The half-life of cyclophosphamide in blood of rats pre-treated with phenobarbital was shorter than in control rats. This change is closely related to higher rates of production of p-nitrobenzylpyridine-positive alkylating metabolites of cyclophosphamide, which in turn is followed by their more rapid disappearance from the circulation. 3. Urinary excretion reflects this situation; lower amounts of cyclophosphamide and higher concentrations of its alkylating metabolites are present in the urine of phenobarbital-treated rats. 4. Perfusion of livers isolated from phenobarbital-pre-treated rats confirmed the results in vivo. With this preparation, too, disappearance of cyclophosphamide was more rapid and formation of its alkylating metabolites was accelerated after phenobarbital treatment.

Alkylating Agents↗

Increased pulmonary collagen synthesis in mice treated with cyclophosphamide.

Cyclophosphamide is a widely used anticancer drug which damages lung tissue and elicits a progressive fibrotic lesion in mice. The early time course of collagen accumulation and the changes in collagen synthesis which may accompany this lung damage and fibrosis have not been reported. The total lung concentration of hydroxyproline, an index of collagen content and the extent of pulmonary fibrosis, was not significantly increased in mice until 12 days after treatment with 200 mg/kg cyclophosphamide. The change in total lung hydroxyproline content was preceded, on Day 6, by an increase in the rate of acid-insoluble hydroxyproline synthesis. This rate remained elevated to Day 21, but was no longer significantly increased by Day 28. The percentage of total protein synthesis devoted to the production of collagen was significantly increased 9 and 12 days after cyclophosphamide, compared to saline-treated controls. The rate of pulmonary non-collagen protein synthesis was significantly decreased 3 days after cyclophosphamide, and increased 6 and 15 days after this treatment. These data indicate that cyclophosphamide-induced increases in pulmonary collagen synthesis precede the accumulation of this protein. Increased collagen synthesis may occur in the absence of changes in overall protein synthesis although cyclophosphamide also alters non-collagen protein synthesis.

Animals↗

Combination of 5-fluorouracil and cyclophosphamide in L1210 and P388 leukemias with changes in optimum treatments as a function of the age of the L1210 tumor at first treatment.

The interaction of 5-fluorouracil and cyclophosphamide in the treatment of L1210 and P388 leukemias was studied using response surface methodology. Single dose treatment of each drug was administered simultaneously or with a 24-hr interval between 5-fluorouracil and cyclophosphamide to the advanced tumors or at various times after L1210 inoculation. While at low doses the action of the combination of the two drugs was greater than expected, there was no therapeutic synergism if the drugs were given together (optimum doses cyclophosphamide 366 mg/kg and 364 mg/kg, respectively, in advanced L1210 and P388 leukemias) or in the early tumor when cyclophosphamide was given 24 hours after 5-fluorouracil. In the advanced tumor, using the regimen employing a 24-hr interval between drugs, therapeutic synergism could be demonstrated (optimum doses 5-fluorouracil 130 mg/kg followed by cyclophosphamide 248 mg/kg in advanced L1210 leukemia and 5-fluorouracil 110 mg/kg followed by cyclophosphamide 263 mg/kg in advanced P388 leukemia). The evidence generated suggested that improved therapy could be found in two separate regions of the treatment space, raising the possibility of more than one mechanism of drug interaction. The location of the optimal treatment depended on the tumor burden at the time treatment was initiated. A shift from one region to the other occurred after 4-6 days of tumor growth when the original inoculum was 10(5) i.p. L1210 cells. Another more obvious conclusion that can be drawn is that treatment was less effective as the tumor became more advanced. The notion that different tumor stages may require different ratios of drugs in a clinically useful combination should receive attention.

Animals↗

Effect of oral vs. parenteral cyclophosphamide on in vitro IgA and IgG production by murine Peyer's patches and cultured jejunal fragments.

The gut associated lymphoid tissue plays an important role in intestinal defenses, food allergy, oral tolerance, and certain intestinal diseases. This study describes the effect of either oral or parenteral cyclophosphamide on IgA and IgG production in the gut. Mice were treated with cyclophosphamide either IV or PO, and Peyer's patch cell cultures were established to evaluate mitogen induced production of IgA and IgG. To evaluate the effect of cyclophosphamide on the plasma cell rich lamina propria, segments of jejunum were cultured and overnight secretion of IgG and IgA were measured. We found, the secretion of IgA or IgG by jejunal fragments was not influenced by cyclophosphamide (IV or PO). Mitogen induced secretion of IgA and IgG by Peyer's patch cells was markedly decreased 24 hrs after drug administration, with significant recovery by day 7. Cell mixing experiments revealed that a single dose cyclophosphamide reduced the capacity of Peyer's patch B cells to secrete IgA or IgG when co cultured with normal T cells. This study demonstrates that a single dose cyclophosphamide can have profound effects on the gut immune system and that the drug has a similar effect when given either orally or parenterally.

Administration, Oral↗

Pegylated liposomal doxorubicin and cyclophosphamide as first-line therapy for patients with metastatic or recurrent breast cancer.

PURPOSE: Pegylated liposomal doxorubicin (PLD) is an active agent for breast cancer. The efficacy and safety of PLD in combination with cyclophosphamide as first-line treatment of metastatic breast cancer (MBC) was evaluated in this phase II study. PATIENTS AND METHODS: Eligible patients had metastatic or recurrent breast cancer with no previous chemotherapy for metastatic disease. Patients were enrolled into 3 sequential cohorts: cohort I (n = 10) received PLD 50 mg/m2 intravenously (I.V.) on day 1 and cyclophosphamide 100 mg/m2 orally on days 1-14 every 28-day cycle; cohort II (n = 20) received PLD 30 mg/m2 plus cyclophosphamide 600 mg/m2 I.V. on day 1 every 21 days; and cohort III (n = 21) received PLD 35 mg/m2 plus cyclophosphamide 600 mg/m2 I.V. on day 1 every 21 days. RESULTS: An objective response was exhibited in 26 of 51 patients (4 complete responses [CRs], 22 partial responses [PRs]; 51%) in the intent-to-treat population and responses were similar among cohorts. The clinical benefit rate (CR plus PR plus stable disease) was 86%. The median duration of response was 35.1 weeks. The most common adverse events were nausea (71%), asthenia (69%), and neutropenia (67%). There was less toxicity in cohort II than in other cohorts. No clinical cardiac toxicity was observed. Only 2 of 20 patients in cohort II (10%) required treatment discontinuation as a result of adverse events. CONCLUSION: First-line combination therapy with PLD and cyclophosphamide is active and well tolerated in patients with MBC. The recommended doses from this study are PLD 30 mg/m2 and cyclophosphamide 600 mg/m2 I.V. every 21 days.

Administration, Oral↗

Intermittent cyclophosphamide for the treatment of autoimmune thrombocytopenia in systemic lupus erythematosus.

STUDY OBJECTIVE: To determine the effect of monthly intravenous cyclophosphamide therapy in patients with systemic lupus erythematosus and autoimmune thrombocytopenia. DESIGN: Uncontrolled, retrospective clinical study. SETTING: Government referral-based research hospital. PATIENTS: Seven patients with systemic lupus erythematosus and 2 or more months of thrombocytopenia refractory to or requiring excessive doses of corticosteroids. Two patients had also failed to respond to splenectomy and repeated intravenous methylprednisolone infusions. Six patients had severe active renal disease at the time of treatment. INTERVENTIONS: Cyclophosphamide, 0.75 to 1.0 g/m2 body surface area, was given intravenously every month for at least 4 months. Prednisone dose ranged between 0.5 to 1.0 mg/kg.d. MEASUREMENTS AND MAIN RESULTS: All seven patients had normal platelet counts within 2 to 18 weeks after cyclophosphamide treatment (one to four doses). Prednisone was tapered to 0.25 mg/kg on alternate days in all patients. All six patients had significant improvement in their renal disease and lupus serologies. Cyclophosphamide was discontinued after four to six doses in five patients. Four patients maintained normal platelet counts on low dose, alternate-day prednisone for a mean of 5.6 years of follow-up. Two patients had recurrence of thrombocytopenia 1 to 3 years after discontinuing cyclophosphamide. CONCLUSIONS: Monthly intravenous cyclophosphamide is potentially useful for the management of autoimmune thrombocytopenia in patients with systemic lupus erythematosus who are refractory to or dependent on unacceptably high doses of corticosteroids, or are experiencing side effects of conventional medical or surgical treatment.

Autoimmune Diseases↗

The effect of fluconazole on cyclophosphamide metabolism in children.

Fluconazole is increasingly used in children receiving chemotherapy. Many of these patients are being treated with cyclophosphamide, which must undergo hepatic metabolism to produce active alkylating species. As a consequence of the cytochrome P-450 inhibitory properties of fluconazole, a potential interaction exists between these two agents that could influence the therapeutic effect of cyclophosphamide. To investigate this interaction, a retrospective case series of patients was chosen from a population of children with a previously established profile of cyclophosphamide metabolism. Twenty-two children who were not receiving other therapy known to influence drug metabolism were selected and analyzed in terms of fluconazole treatment; of these, nine were receiving fluconazole and thirteen were identified as controls. Study design was not randomized. The plasma clearance of cyclophosphamide was lower in patients receiving fluconazole [mean(SD) 2.4(0.71) versus 4.2(1.2) l/h/m2, p =.001]. In vitro studies were performed to characterize the interaction between fluconazole and cyclophosphamide in six human liver microsomes. The concentration of fluconazole required to reduce the production of 4-hydroxycyclophosphamide to 50% of control values (IC50) varied between 9 and 80 microM (median 38 microM). Further studies of the effect of fluconazole on 4-hydroxycyclophosphamide production in vivo are warranted to determine whether this interaction reduces the therapeutic effect of cyclophosphamide in clinical practice.

Adolescent↗