英文药名: Droxia(Hydroxyurea Capsules) 中文参考药名: 羟基脲胶囊 【药品名称】 【药品名称】:羟基脲 【英文名:Hydroxycarbamide 【中文别名:氨基甲酰基羟胺、氨甲酰基胺、羟基脲素、羟脲 【英文别名】:Hudura、Hydrea、Hydroxicarbamidum、Hydroxyurea、Idroxicarbamidum 【别名】:氨基甲酰基羟胺、氨甲酰基胺、羟基脲素、羟脲、Hudura、Hydrea、Hydroxicarbamidum、Hydroxyurea、Idroxicarbamidum 【性状】:本品为白色结晶性粉末;无臭,味微涩。本品在水中易溶,在乙醇中微溶,在乙醚中不溶。 熔点: 本品的熔点为138~145℃,熔融时同时分解。
【药物动力学】 本品口服吸收较快,2小时后血清浓度已达高峰,6小时后消失,T1/2为3~4小时,可透过血脑屏障。主要在肝内代谢,由尿中排泄,4小时内能排出60%,12小时内80%。
【适应症】 主要用于治疗慢性粒细胞白血病(慢粒)、慢粒的加速期和急变期、真性红细胞增多症,另对头颈部原发性鳞癌、复发性转移性卵巢癌等亦有一定疗效; 与放射治疗同时应用或作为放射增敏剂,可增加治疗头颈部肿瘤的疗效。 【用法用量】 1.成人常用量 ①慢粒,可根据患者用药前病情及白细胞数高低而决定剂量,一般开始剂量为每日按体重20—30mg/kg,1次或分2次口服,当白细胞下降至10×109/L以下时减量至约为每日20mg/kg,口服维持或改间歇服用。 ②头颈癌、卵巢癌等,剂量为每次按体重60—80mg/kg或按体表面积2000—3000mg/平方米,每3日口服1次,单独服用或与放疗合用;亦可每日按体重20—30mg/kg,每日1次口服给药。 2. 小儿常用量尚未确定。 (1)对饮食牛奶、乳糖或对酒石黄(tartrazine)不能忍受者,对服用以乳糖或酒石黄作为赋形剂的本品胶囊亦可能不能忍受。 (2)患者避免接受死(或活)病毒疫苗的免疫接种,由于服用本品会使患者的免疫机制受抑制,对接种疫苗后产生抗体的反应亦减弱,且要经3个月后才能恢复,因而要停用本品3个月到1年后才可以考虑接种疫苗。本品与活病毒同时合用时,会增强病毒的增殖能力与毒性,因而白血病患者在获完全缓解后离最后一次化疗日3个月以上才能考虑活病毒疫苗接种。与患者密切接触的家属成员等亦应延缓口服脊髓灰质炎疫苗。 (3)服用本品时应适量增加液体的摄入量,以增加尿量及尿酸的排出。 (4)治疗前后及治疗期要严密定期随访血常规、血小板计数、血尿素氮、尿酸、肌酐浓度。 (5)本品的使用剂量必须根据患者对治疗的反应、耐受性等而调节。 (6)若服用本品已达6周仍未见效,应考虑停服本品而改换其他药物治疗。 (7)在服用本品过程中,若出现显著的粒细胞或血小板减低,例如白细胞下降至2.5×109/L或血小板下降至100×109/L以下,应暂停服用本品,并予相应的处理。 (8)与放疗合用时,应在放疗前7日开始给药,并严密观察血象,若出现严重的放疗不良反险亦应考虑减少或暂停服用本品。 任何疑问,请遵医嘱! 【不良反应】 (1)造血系统:较常见的有白细胞减少、贫血或红细胞形态的异常。白细胞减低通常在治疗开始约10日后发生,少数可合并感染,红细胞可出现巨幼红改变,形态类似恶性贫血,但其发生与维生素Bl2或叶酸缺乏无关。患者的血清铁清除率迟缓、红细胞对铁利用率减少。较少的有血小板减少。 (2)消化系统:较常见的有胃纳减退、恶心、呕吐,较少见的有便秘,长期服用本品可发生口腔粘膜炎、口腔溃疡等。 (3)其它:皮疹、红斑、瘙痒等皮肤反应及脱发较为少见,可偶然发生由于大量白细胞迅速崩溃而引起的血尿酸增高或尿酸性肾病,偶然可见到头痛、倦睡、头晕、幻觉、惊厥等神经毒性表现。骨髓抑制,白细胞及血小板减少.药热,胃肠道反应.有报道可引起睾丸缩小及致畸胎作用。其他还有色素沉着、超敏反应、局部损伤及对射线过敏等等。 【禁忌】 (1)由于本品有诱变、致畸胎、致癌的潜在可能,故应避免在妊娠初期的3个月内或哺乳期内服用。 (2)老年患者对本品较敏感,且肾功能可能较差,故服用本品时应适当减少剂量。 (3)下列情况禁用:水痘、带状疱疹及各种严重感染。下列情况应慎用:严重贫血未纠正前、骨髓抑制、肾功能不全、痛风、尿酸盐结石史等。有报道可引起睾丸缩小及致畸胎作用。 【药物相互作用】 (1)由于本品有可能提高服用者血尿酸的浓度,因此与别嘌醇、秋水仙碱、丙磺舒等合用治疗痛风时,必须调节上述抗痛风药物剂量,以控制痛风病变及血尿酸的浓度。本品与别嘌醇合用时能预防并逆转本品所致的高尿酸血症。 (2)与能引起白细胞或血小板减低的药物或放射疗法联合应用时,应严密观察患者的血象,并根据血白细胞及血小板数适当调节羟基脲的用量。 (3)本品与烷化剂和放射线无交叉耐药性。 【规格】 羟基脲500mg (1).抗癌:一日40-60mg/kg,一周2次,一疗程6周.可大剂量间歇给药,每8小时1次,剂量60mg/kg,或6小时1次,剂量100mg/kg,24小时一疗程,间歇4-7天. (2).顽固和脓疱性银屑病:日0.5-1.5g,4-8周一疗程.
DESCRIPTION
DROXIA® (hydroxyurea capsules, USP) is available for oral use as capsules providing 200 mg, 300 mg, and 400 mg hydroxyurea. Inactive ingredients: citric acid, gelatin, lactose, magnesium stearate, sodium phosphate, titanium dioxide, and capsule colorants; FD&C Blue #1 and FD&C Green #3 (200 mg capsules); D&C Red #28, D&C Red #33, and FD&C Blue #1 (300 mg capsules); D&C Red #28, D&C Red #33, and D&C Yellow #10 (400 mg capsules).
Hydroxyurea is an essentially tasteless, white crystalline powder. Its structural formula is:
CLINICAL PHARMACOLOGY
Mechanism of Action
The precise mechanism by which hydroxyurea produces its cytotoxic and cytoreductive effects is not known. However, various studies support the hypothesis that hydroxyurea causes an immediate inhibition of DNA synthesis by acting as a ribonucleotide reductase inhibitor, without interfering with the synthesis of ribonucleic acid or of protein.
The mechanisms by which DROXIA produces its beneficial effects in patients with sickle cell anemia (SCA) are uncertain. Known pharmacologic effects of DROXIA that may contribute to its beneficial effects include increasing hemoglobin F levels in RBCs, decreasing neutrophils, increasing the water content of RBCs, increasing deformability of sickled cells, and altering the adhesion of RBCs to endothelium.
Pharmacokinetics
Absorption
Hydroxyurea is readily absorbed after oral administration. Peak plasma levels are reached in 1 to 4 hours after an oral dose. With increasing doses, disproportionately greater mean peak plasma concentrations and AUCs are observed.
There are no data on the effect of food on the absorption of hydroxyurea.
Distribution
Hydroxyurea distributes rapidly and widely in the body with an estimated volume of distribution approximating total body water.
Plasma to ascites fluid ratios range from 2:1 to 7.5:1. Hydroxyurea concentrates in leukocytes and erythrocytes.
Metabolism
Up to 60% of an oral dose undergoes conversion through metabolic pathways that are not fully characterized. One pathway is probably saturable hepatic metabolism. Another minor pathway may be degradation by urease found in intestinal bacteria. Acetohydroxamic acid was found in the serum of three leukemic patients receiving hydroxyurea and may be formed from hydroxylamine resulting from action of urease on hydroxyurea.
Excretion
Excretion of hydroxyurea in humans is likely a linear first-order renal process. In adults with SCA, mean cumulative urinary recovery of hydroxyurea was about 40% of the administered dose.
Special Populations
Geriatric, Gender, Race
No information is available regarding pharmacokinetic differences due to age, gender, or race.
Pediatric
No pharmacokinetic data are available in pediatric patients treated with hydroxyurea for SCA.
Renal Insufficiency
As renal excretion is a pathway of elimination, consideration should be given to decreasing the dosage of hydroxyurea in patients with renal impairment. In adult patients with sickle cell disease, an open-label, non-randomized, single-dose, multicenter study was conducted to assess the influence of renal function on the pharmacokinetics of hydroxyurea. Patients in the study with normal renal function (creatinine clearance [CrCl] >80 mL/min), mild (CrCl 50-80 mL/min), moderate (CrCl = 30-<50 mL/min), or severe (<30 mL/min) renal impairment received hydroxyurea as a single oral dose of 15 mg/kg, achieved by using combinations of the 200 mg, 300 mg, or 400 mg capsules. Patients with end-stage renal disease (ESRD) received two doses of 15 mg/kg separated by 7 days, the first was given following a 4-hour hemodialysis session, the second prior to hemodialysis. In this study, the mean exposure (AUC) in patients whose creatinine clearance was <60 mL/min (or ESRD) was approximately 64% higher than in patients with normal renal function. The results suggest that the initial dose of hydroxyurea should be reduced when used to treat patients with renal impairment. (See PRECAUTIONS and DOSAGE AND ADMINISTRATION.) The table below describes the recommended dosage modification.
On dialysis days, hydroxyurea should be administered to patients with ESRD following hemodialysis. |
Creatinine Clearance (mL/min) |
Recommended DROXIA Initial Dose (mg/kg daily) |
≥60 |
15 |
<60 or ESRD* |
7.5 | Close monitoring of hematologic parameters is advised in these patients.
Hepatic Insufficiency
There are no data that support specific guidance for dosage adjustment in patients with hepatic impairment. Close monitoring of hematologic parameters is advised in these patients.
Drug Interactions
There are no data on concomitant use of hydroxyurea with other drugs in humans.
Clinical Studies
The efficacy of hydroxyurea in sickle cell anemia was assessed in a large clinical study (Multicenter Study of Hydroxyurea in Sickle Cell Anemia).1
The study was a randomized, double-blind, placebo-controlled trial that evaluated 299 adult patients (≥18 years) with moderate to severe disease (≥3 painful crises yearly). The trial was stopped by the Data Safety Monitoring Committee, after accrual was completed but before the scheduled 24 months of follow-up was completed in all patients, based on observations of fewer painful crises among patients receiving hydroxyurea.
Compared to placebo treatment, treatment with hydroxyurea resulted in a significant decrease in the yearly rate of painful crises, the yearly rate of painful crises requiring hospitalization, the incidence of chest syndrome, the number of patients transfused, and units of blood transfused. Hydroxyurea treatment significantly increased the median time to both first and second painful crises.
Although patients with 3 or more painful crises during the preceding 12 months were eligible for the study, most of the benefit in crisis reduction was seen in the patients with 6 or more painful crises during the preceding 12 months.
EVENT |
HYDROXYUREA (N=152) |
PLACEBO (N=147) |
PERCENT CHANGE VS PLACEBO |
P-VALUE |
A painful crisis was defined in the study as acute sickling-related pain that resulted in a visit to a medical facility, that lasted more than 4 hours, and that required treatment with a parenteral narcotic or NSAID. Chest syndrome, priapism, and hepatic sequestration were also included in this definition. |
Median yearly rate of painful crises |
2.5 |
4.6 |
-46 |
=0.001 |
Median yearly rate of painful crises requiring hospitalization |
1.0 |
2.5 |
-60 |
=0.0027 |
Median time to first painful crisis (months) |
2.76 |
1.35 |
+104 |
=0.014 |
Median time to second painful crisis (months) |
6.58 |
4.13 |
+59 |
=0.0024 |
Incidence of chest syndrome (episodes) |
56 |
101 |
-45 |
=0.003 |
Number of patients transfused |
55 |
79 |
-30 |
=0.002 |
Number of units of blood transfused |
423 |
670 |
-37 |
=0.003 | No deaths were attributed to treatment with hydroxyurea, and none of the patients developed neoplastic disorders during the study. Treatment was permanently stopped for medical reasons in 14 hydroxyurea-treated (2 patients with myelotoxicity) and 6 placebo-treated patients. (See ADVERSE REACTIONS.)
Fetal Hemoglobin
In patients with SCA treated with hydroxyurea, fetal hemoglobin (HbF) increases 4 to 12 weeks after initiation of treatment. In general, average HbF levels correlate with dose and plasma level with possible plateauing at higher dosages.
A clear relation between reduction in crisis frequency and increased HbF or F-cell levels has not been demonstrated. The dose-related cytoreductive effects of hydroxyurea, particularly on neutrophils, was the factor most strongly correlated with reduced crisis frequency.
INDICATIONS AND USAGE
DROXIA (hydroxyurea capsules, USP) is indicated to reduce the frequency of painful crises and to reduce the need for blood transfusions in adult patients with sickle cell anemia with recurrent moderate to severe painful crises (generally at least 3 during the preceding 12 months).
CONTRAINDICATIONS
DROXIA is contraindicated in patients who have demonstrated a previous hypersensitivity to hydroxyurea or any other component of its formulation.
WARNINGS
DROXIA is a cytotoxic and myelosuppressive agent. DROXIA should not be given if bone marrow function is markedly depressed, as indicated by neutrophils below 2000 cells/mm3; a platelet count below 80,000/mm3; a hemoglobin level below 4.5 g/dL; or reticulocytes below 80,000/mm3 when the hemoglobin concentration is below 9 g/dL. Neutropenia is generally the first and most common manifestation of hematologic suppression. (See DOSAGE AND ADMINISTRATION.) Thrombocytopenia and anemia occur less often, and are seldom seen without a preceding leukopenia. Recovery from myelosuppression is usually rapid when therapy is interrupted. DROXIA causes macrocytosis, which may mask the incidental development of folic acid deficiency. Prophylactic administration of folic acid is recommended.
In HIV-infected patients during therapy with hydroxyurea and didanosine, with or without stavudine, fatal and nonfatal pancreatitis have occurred. Hepatotoxicity and hepatic failure resulting in death have been reported during post-marketing surveillance in HIV-infected patients treated with hydroxyurea and other antiretroviral agents. Fatal hepatic events were reported most often in patients treated with the combination of hydroxyurea, didanosine, and stavudine. This combination should be avoided.
Peripheral neuropathy, which was severe in some cases, has been reported in HIV-infected patients receiving hydroxyurea in combination with antiretroviral agents, including didanosine, with or without stavudine.
Cutaneous vasculitic toxicities, including vasculitic ulcerations and gangrene, have occurred in patients with myeloproliferative disorders during therapy with hydroxyurea. These vasculitic toxicities were reported most often in patients with a history of, or currently receiving, interferon therapy. Due to potentially severe clinical outcomes for the cutaneous vasculitic ulcers reported in patients with myeloproliferative disease, hydroxyurea should be discontinued if cutaneous vasculitic ulcerations develop.
Carcinogenesis and Mutagenesis
(See BOXED WARNING.)
Hydroxyurea is genotoxic in a wide range of test systems and is thus presumed to be a human carcinogen. In patients receiving long-term hydroxyurea for myeloproliferative disorders, such as polycythemia vera and thrombocythemia, secondary leukemia has been reported. It is unknown whether this leukemogenic effect is secondary to hydroxyurea or is associated with the patient’s underlying disease. Skin cancer has also been reported in patients receiving long-term hydroxyurea.
Conventional long-term studies to evaluate the carcinogenic potential of DROXIA have not been performed. However, intraperitoneal administration of 125 to 250 mg/kg hydroxyurea (about 0.6-1.2 times the maximum recommended human oral daily dose on a mg/m2 basis) thrice weekly for 6 months to female rats increased the incidence of mammary tumors in rats surviving to 18 months compared to control. Hydroxyurea is mutagenic in vitro to bacteria, fungi, protozoa, and mammalian cells. Hydroxyurea is clastogenic in vitro (hamster cells, human lymphoblasts) and in vivo (SCE assay in rodents, mouse micronucleus assay). Hydroxyurea causes the transformation of rodent embryo cells to a tumorigenic phenotype.
Pregnancy
DROXIA can cause fetal harm when administered to a pregnant woman. Hydroxyurea has been demonstrated to be a potent teratogen in a wide variety of animal models, including mice, hamsters, cats, miniature swine, dogs, and monkeys at doses within 1-fold of the human dose given on a mg/m2 basis. Hydroxyurea is embryotoxic and causes fetal malformations (partially ossified cranial bones, absence of eye sockets, hydrocephaly, bipartite sternebrae, missing lumbar vertebrae) at 180 mg/kg/day (about 0.8 times the maximum recommended human daily dose on a mg/m2 basis) in rats and at 30 mg/kg/day (about 0.3 times the maximum recommended human daily dose on a mg/m2 basis) in rabbits. Embryotoxicity was characterized by decreased fetal viability, reduced live litter sizes, and developmental delays. Hydroxyurea crosses the placenta. Single doses of ≥375 mg/kg (about 1.7 times the maximum recommended human daily dose on a mg/m2 basis) to rats caused growth retardation and impaired learning ability. There are no adequate and well-controlled studies in pregnant women. If this drug is used during pregnancy or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential harm to the fetus. Women of childbearing potential should be advised to avoid becoming pregnant.
PRECAUTIONS
General
Therapy with DROXIA requires close supervision. Some patients treated at the recommended initial dose of 15 mg/kg/day have experienced severe or life-threatening myelosuppression, requiring interruption of treatment and dose reduction. The hematologic status of the patient, as well as kidney and liver function should be determined prior to, and repeatedly during treatment. Treatment should be interrupted if neutrophil levels fall to <2000/mm3; platelets fall to <80,000/mm3; hemoglobin declines to less than 4.5 g/dL; or if reticulocytes fall below 80,000/mm3 when the hemoglobin concentration is below 9 g/dL. Following recovery, treatment may be resumed at lower doses (see DOSAGE AND ADMINISTRATION).
Hydroxyurea should be used with caution in patients with renal dysfunction. Data from a single-dose study of the pharmacokinetics of hydroxyurea in patients with sickle cell anemia suggest that the initial dose of hydroxyurea should be reduced in patients with renal impairment. (See CLINICAL PHARMACOLOGY: Special Populations and DOSAGE AND ADMINISTRATION.)
Patients must be able to follow directions regarding drug administration and their monitoring and care.
Hydroxyurea is not indicated for the treatment of HIV infection; however, if HIV-infected patients are treated with hydroxyurea, and in particular, in combination with didanosine and/or stavudine, close monitoring for signs and symptoms of pancreatitis is recommended. Patients who develop signs and symptoms of pancreatitis should permanently discontinue therapy with hydroxyurea. (See WARNINGS and ADVERSE REACTIONS.)
An increased risk of hepatotoxicity, which may be fatal, may occur in patients treated with hydroxyurea, and in particular, in combination with didanosine and stavudine. This combination should be avoided.
Carcinogenesis, Mutagenesis, Impairment of Fertility
See WARNINGS and BOXED WARNING for Carcinogenesis and Mutagenesis information.
Impairment of Fertility: Hydroxyurea administered to male rats at 60 mg/kg/day (about 0.3 times the maximum recommended human daily dose on a mg/m2 basis) produced testicular atrophy, decreased spermatogenesis, and significantly reduced their ability to impregnate females.
Pregnancy
Pregnancy Category D. (See WARNINGS.)
Nursing Mothers
Hydroxyurea is excreted in human milk. Because of the potential for serious adverse reactions with hydroxyurea, a decision should be made either to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
Pediatric Use
Safety and effectiveness in pediatric patients have not been established.
Drug Interactions
Prospective studies on the potential for hydroxyurea to interact with other drugs have not been performed.
Information for Patients
(See Patient Information at end of labeling.)
Patients should be reminded that this medication must be handled with care. People who are not taking DROXIA should not be exposed to it. To decrease the risk of exposure, wear disposable gloves when handling DROXIA or bottles containing DROXIA. Anyone handling DROXIA should wash their hands before and after contact with the bottle or capsules. If the powder from the capsule is spilled, it should be wiped up immediately with a damp disposable towel and discarded in a closed container, such as a plastic bag. The medication should be kept away from children and pets. Contact your doctor for instructions on how to dispose of outdated capsules.
The necessity of monitoring blood counts every two weeks, throughout the duration of therapy, should be emphasized. For additional information, see the accompanying Patient Information leaflet.
ADVERSE REACTIONS
Sickle Cell Anemia
In patients treated for sickle cell anemia in the Multicenter Study of Hydroxyurea in Sickle Cell Anemia,1 the most common adverse reactions were hematologic, with neutropenia, and low reticulocyte and platelet levels necessitating temporary cessation in almost all patients. Hematologic recovery usually occurred in two weeks.
Non-hematologic events that possibly were associated with treatment include hair loss, skin rash, fever, gastrointestinal disturbances, weight gain, bleeding, and parvovirus B-19 infection; however, these non-hematologic events occurred with similar frequencies in the hydroxyurea and placebo treatment groups. Melanonychia has also been reported in patients receiving DROXIA for SCA.
Other
Adverse events associated with the use of hydroxyurea in the treatment of neoplastic diseases, in addition to hematologic effects include: gastrointestinal symptoms (stomatitis, anorexia, nausea, vomiting, diarrhea, and constipation), and dermatological reactions such as maculopapular rash, skin ulceration, dermatomyositis-like skin changes, peripheral erythema, and facial erythema. Hyperpigmentation, atrophy of skin and nails, scaling, and violet papules have been observed in some patients after several years of long-term daily maintenance therapy with hydroxyurea. Skin cancer has been reported. Cutaneous vasculitic toxicities, including vasculitic ulcerations and gangrene, have occurred in patients with myeloproliferative disorders during therapy with hydroxyurea. These vasculitic toxicities were reported most often in patients with a history of, or currently receiving, interferon therapy (see WARNINGS). Dysuria and alopecia have been reported. Large doses may produce drowsiness. Neurological disturbances have occurred and were limited to headache, dizziness, disorientation, hallucinations, and convulsions. Hydroxyurea may cause temporary impairment of renal tubular function accompanied by elevations in serum uric acid, blood urea nitrogen (BUN), and creatinine levels. Abnormal bromsulphalein (BSP) retention has been reported. Fever, chills, malaise, edema, asthenia, and elevation of hepatic enzymes have also been reported.
The association of hydroxyurea with the development of acute pulmonary reactions consisting of diffuse pulmonary infiltrates, fever, and dyspnea has been reported. Pulmonary fibrosis also has been reported.
In HIV-infected patients who received hydroxyurea in combination with antiretroviral agents, in particular, didanosine plus stavudine, fatal and nonfatal pancreatitis and hepatotoxicity, and severe peripheral neuropathy have been reported. Patients treated with hydroxyurea in combination with didanosine, stavudine, and indinavir in Study ACTG 5025 showed a median decline in CD4 cells of approximately 100/mm3. (SeeWARNINGS and PRECAUTIONS.)
OVERDOSAGE
Acute mucocutaneous toxicity has been reported in patients receiving hydroxyurea at dosages several times the therapeutic dose. Soreness, violet erythema, edema on palms and soles followed by scaling of hands and feet, severe generalized hyperpigmentation of the skin, and stomatitis have been observed.
DOSAGE AND ADMINISTRATION
Procedures for proper handling and disposal of cytotoxic drugs should be considered. Several guidelines on this subject have been published.2-5
To minimize the risk of dermal exposure, always wear impervious gloves when handling bottles containing DROXIA capsules. DROXIA capsules should not be opened. Personnel should avoid exposure to crushed or opened capsules. If contact with crushed or opened capsules occurs, wash immediately and thoroughly. More information is available in the references listed below.
Dosage should be based on the patient’s actual or ideal weight, whichever is less. The initial dose of DROXIA is 15 mg/kg/day as a single dose. The patient’s blood count must be monitored every two weeks. (See WARNINGS.)
If blood counts are in an acceptable range, the dose may be increased by 5 mg/kg/day every 12 weeks until a maximum tolerated dose (the highest dose that does not produce toxicblood counts over 24 consecutive weeks), or 35 mg/kg/day, is reached.
If blood counts are between the acceptable range* and toxic**, the dose is not increased.
If blood counts are considered toxic, DROXIA should be discontinued until hematologic recovery. Treatment may then be resumed after reducing the dose by 2.5 mg/kg/day from the dose associated with hematologic toxicity. DROXIA may then be titrated up or down, every 12 weeks in 2.5 mg/kg/day increments, until the patient is at a stable dose that does not result in hematologic toxicity for 24 weeks. Any dosage on which a patient develops hematologic toxicity twice should not be tried again.
acceptable range = neutrophils ≥2500 cells/mm3, platelets ≥95,000/mm3, hemoglobin >5.3 g/dL and reticulocytes ≥95,000/mm3 if the hemoglobin concentration <9 g/dL.
toxic = neutrophils <2000 cells/mm3, platelets <80,000/mm3, hemoglobin <4.5 g/dL and reticulocytes <80,000/mm3 if the hemoglobin concentration <9 g/dL.
Renal Insufficiency
As renal excretion is a pathway of elimination, consideration should be given to decreasing the dosage of DROXIA in patients with renal impairment. The results of a single-dose study of the influence of renal function on the pharmacokinetics of hydroxyurea in adults with sickle cell disease suggest that the initial dose of hydroxyurea should be reduced by 50%, to 7.5 mg/kg/day, when used to treat patients with renal impairment. (See PRECAUTIONS and CLINICAL PHARMACOLOGY.) Close monitoring of hematologic parameters is advised in these patients.
On dialysis days, hydroxyurea should be administered to patients with ESRD following hemodialysis. |
Creatinine Clearance (mL/min) |
Recommended DROXIA Initial Dose (mg/kg daily) |
≥60 |
15 |
<60 or ESRD |
7.5 | Hepatic Insufficiency
There are no data that support specific guidance for dosage adjustment in patients with hepatic impairment. Close monitoring of hematologic parameters is advised in these patients.
HOW SUPPLIED
DROXIA® (hydroxyurea capsules, USP).
200 mg capsules packaged in HDPE bottles of 60 with a plastic safety screw cap. (NDC 0003-6335-17). The cap and body are opaque blue-green. The capsule is marked in black ink on both the cap and body with “DROXIA” and “6335”.
300 mg capsules packaged in HDPE bottles of 60 with a plastic safety screw cap. (NDC 0003-6336-17). The cap and body are opaque purple. The capsule is marked in black ink on both the cap and body with “DROXIA” and “6336”.
400 mg capsules packaged in HDPE bottles of 60 with a plastic safety screw cap. (NDC 0003-6337-17). The cap and body are opaque reddish-orange. The capsule is marked in black ink on both the cap and body with “DROXIA” and “6337”.
Storage
Store at 25°C (77°F); excursions permitted to 15-30°C (59-86°F) [see USP Controlled Room Temperature]. Keep tightly closed.
REFERENCES
- Charache S, Barton FB, Moore RD, et al; Hydroxyurea and sickle cell anemia: clinical utility of a myelosuppressive "switching" agent. Medicine. 1996;75:300-326.
- NIOSH Alert: Preventing occupational exposures to antineoplastic and other hazardous drugs in healthcare settings. 2004. U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2004-165.
- OSHA Technical Manual, TED 1-0.15A, Section VI: Chapter 2. Controlling Occupational Exposure to Hazardous Drugs. OSHA, 1999. http://www.osha.gov/dts/osta/otm/otm_vi/otm_vi_2.html
- American Society of Health-System Pharmacists. ASHP guidelines on handling hazardous drugs. Am J Health-Syst Pharm. 2006;63:1172-1193.
- Polovich M, White JM, Kelleher LO, eds. 2005. Chemotherapy and biotherapy guidelines and recommendations for practice (2nd ed.) Pittsburgh, PA: Oncology Nursing Society.
Manufactured for:
Bristol-Myers Squibb Company Princeton, New Jersey 08543 USA Made in Italy 1053547A6 Rev May 2010
Patient Information About DROXIA® Capsules (generic name = hydroxyurea)
What is the most important information I should know about DROXIA? DROXIA (pronounced drock-SEE-yuh) capsules are used to treat sickle cell anemia in adults. DROXIA reduces the frequency of painful crises and reduces the need for blood transfusions. It is VERY IMPORTANT that you have regular blood counts so that your doctor can decrease or increase the DROXIA dose as needed to avoid serious complications. The most serious side effects of DROXIA involve the blood and may include severely low white blood cell counts (leukopenia, neutropenia), which can decrease your resistance to infections, severely low red blood cell counts (anemia), or severely low platelet counts (thrombocytopenia), which can cause bleeding. Almost all patients who received DROXIA in clinical studies needed to have their medication stopped for a time to allow their low blood counts to return to acceptable levels. If you get pregnant, DROXIA may harm or cause death to your unborn child. You should not become pregnant while taking DROXIA. Make sure you use a contraceptive method. Tell your doctor if you become pregnant or plan to become pregnant while taking DROXIA. DROXIA may decrease the ability of men to father children and women to have children. Laboratory tests and reports in humans suggest DROXIA may increase your risk of developing cancer, especially if it is taken for a long time. However, it is still uncertain whether DROXIA causes cancer. |
What is DROXIA?
DROXIA (hydroxyurea capsules, USP) is a prescription medicine that is used to reduce the frequency of painful crises and reduce the need for blood transfusions in adults with sickle cell anemia. How DROXIA works is not certain but it may work by reducing the number of white blood cells and/or increasing red blood cells that carry fetal hemoglobin (HbF). Fetal hemoglobin may prevent sickling.
What is Sickle Cell Anemia?
Sickle cell anemia is an inherited disorder of the red blood cells. Red blood cells carry oxygen to all parts of the body by using a protein called hemoglobin. Normal red blood cells contain only normal hemoglobin and are shaped like indented disks. These cells are very flexible and move easily through small blood vessels.
In sickle cell anemia, the red blood cells contain sickle hemoglobin, which causes them to change to a rigid, spiked shape (sickle shape) after oxygen is released. Sickled cells get stuck and form plugs in small blood vessels. These plugs restrict blood flow, causing damage to surrounding tissues resulting in a painful crisis.
Because there are blood vessels in all parts of the body, painful crises can occur anywhere in your body. In addition, sickle cells are trapped and destroyed in the liver and spleen. This results in a shortage of red blood cells (anemia).
Will DROXIA cure my Sickle Cell Anemia?
No. However, DROXIA may help you better control your sickle cell anemia, but it is important to follow your doctor’s instructions carefully.
In a study of adults taking recommended doses, daily treatment with DROXIA resulted in fewer painful crises, fewer patients with “acute chest syndrome” (a pneumonia-like condition that leads to difficulty in breathing) and less need for blood transfusions.
Who should not take DROXIA capsules?
Do not take DROXIA capsules if you are allergic to any of the ingredients. Besides the active ingredient hydroxyurea, DROXIA capsules contain the following inactive ingredients: citric acid, gelatin, lactose, magnesium stearate, sodium phosphate, titanium dioxide, and capsule colorants. Tell your doctor if you think you have ever had an allergic reaction.
If you get pregnant, DROXIA may harm or cause death to your unborn child. You should not become pregnant while taking DROXIA. Make sure you use a contraceptive method. Tell your doctor if you become pregnant or plan to become pregnant while taking DROXIA.
How do I take DROXIA capsules?
Always follow your doctor’s instructions carefully when taking DROXIA capsules or any prescription medication. The usual dose of DROXIA may range from as few as one to several capsules per day. DROXIA is usually taken once a day. You should try to take it at the same time each day. Your doctor will determine the proper starting dose of DROXIA for you based on your weight and blood count. The dose will then be increased slowly to your maximum tolerated dose (maximum dose that does NOT produce severely low blood counts). Your doctor should measure your blood counts every two weeks after you begin treatment with DROXIA. Depending on the results, your dosage may be adjusted or the drug may be stopped for a while.
If you accidentally take an overdose of DROXIA capsules, seek medical attention immediately. Contact your doctor, local Poison Control Center, or emergency room.
How do I handle DROXIA capsules safely?
DROXIA is a medication that must be handled with care. People who are not taking DROXIA should not be exposed to it. To decrease the risk of exposure, wear disposable gloves when handling DROXIA or bottles containing DROXIA. Anyone handling DROXIA should wash their hands before and after contact with the bottle or capsules. If the powder from the capsule is spilled, it should be wiped up immediately with a damp disposable towel and discarded in a closed container, such as a plastic bag. DROXIA should be kept out of the reach of children and pets. Contact your doctor or pharmacist for instructions on how to dispose of outdated capsules.
What if I miss a dose of DROXIA capsules?
Try not to miss your dose of DROXIA, but if you do, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses during the same day. If you miss more than one dose, call your doctor for instructions.
What should I avoid while taking DROXIA capsules?
Some other medications can increase your risk of experiencing serious side effects from DROXIA. While you are taking DROXIA capsules, you should inform your doctor of all prescription and over-the-counter medicines that you are taking.
In nursing mothers, DROXIA is present in breast milk. Because of the potential for side effects in the newborn, you should discontinue nursing your baby while taking DROXIA.
What are the possible side effects of DROXIA capsules?
As with other medicines, DROXIA may cause unwanted effects, although it is not always possible to tell whether such effects are caused by DROXIA, another medication you may be taking, or your sickle cell anemia. Any side effects or unusual symptoms that you experience should be reported to your doctor, particularly if they persist or are troublesome.
The most serious side effects of DROXIA involve the blood, and may include severely low white blood cell counts (leukopenia, neutropenia), which can decrease your resistance to infections, severely low red blood cell counts (anemia), or severely low platelet counts (thrombocytopenia), which can cause bleeding. Almost all patients who received DROXIA in clinical studies needed to have their medication stopped for a time to allow their low blood counts to return to acceptable levels.
The side effects reported most often by adults with sickle cell anemia participating in studies of DROXIA included hair loss, skin rash, fever, stomach and/or bowel disturbances, weight gain, bleeding, virus infection, and discolored nails (melanonychia), but these were equally common in people getting a placebo (sugar pill).
Skin cancer and leukemia, which can be fatal, have been reported in patients receiving long-term hydroxyurea for conditions other than sickle cell anemia. In laboratory tests, DROXIA causes changes in chromosomes and DNA (genetic material) that strongly suggest it can cause cancer in people, especially if it is taken for a long time.
Skin ulcers have been seen in patients taking DROXIA therapy. Contact your doctor if skin ulcers develop while you are taking DROXIA.
Are regular blood counts necessary while taking DROXIA capsules?
Yes. Your doctor should measure your blood counts every two weeks while you are taking DROXIA. Your DROXIA dose will require adjustment based on these regular blood counts. Serious problems can occur if the DROXIA dose is not adjusted on time.
What else should I know about DROXIA capsules?
If you have kidney or liver disease, close monitoring of your blood count, kidney and liver function will be required. If you have kidney disease, your dose of DROXIA may be started at a lower level and increased gradually.
Because it may not be possible to detect a deficiency of folic acid in patients taking DROXIA, your doctor may prescribe a folic acid supplement for you.
What else should I do to control my sickle cell crises?
Because painful crises can be brought on by factors such as infection, dehydration, worsening anemia, emotional stress, extreme temperature exposure, or ingestion of substances such as alcohol or other recreational drugs, you should be aware of the following general guidelines that will help keep you pain-free:
- Seek immediate medical attention when a fever develops or signs of infection appear.
- Avoid smoking and drinking more than 1 to 2 alcoholic beverages a day.
- Drink 8 to 10 glasses of water or other fluid each day.
- Avoid any types of physical exertion that seem to bring on painful crises or other discomfort.
- Avoid extreme temperature changes and dress appropriately in hot and cold weather.
What should I know if I am HIV-positive?
Because of serious, life-threatening side effects associated with DROXIA used in combination with certain medications for HIV, your doctor should closely monitor your pancreas and liver function with frequent physical examinations and laboratory blood tests. The combination of DROXIA, ZERIT® (stavudine) and VIDEX® (didanosine) should be avoided. Some studies have shown a decrease in the number of CD4 (T-cells) for HIV-positive patients taking DROXIA. Although DROXIA is approved by the U.S. Food and Drug Administration for treating sickle cell anemia, it is not approved for treating HIV infection.
This medicine was prescribed for your particular condition. Do not use DROXIA capsules for another condition or give it to others.
This summary does not include everything there is to know about DROXIA capsules. Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. If you have questions or concerns, or want more information about DROXIA capsules, your physician and pharmacist have the complete prescribing information upon which this guide is based. You may want to read it and discuss it with your doctor. Remember, no written summary can replace careful discussion with your doctor.
This Patient Information has been approved by the U.S. Food and Drug Administration.
Manufactured for:
Bristol-Myers Squibb Company Princeton, New Jersey 08543 USA Made in Italy
1053547A6 Rev May 2010
----------------------------------------- REPRESENTATIVE PACKAGING
See How Supplied section for a complete list of available packages of DROXIA.
60 CAPSULES NDC 0003-6335-17 DROXIA® (hydroxyurea capsules, USP) 200 mg per capsule Rx only Bristol-Myers Squibb |