Biomedical subjects

H A Liebman

Publications and source records attributed to H A Liebman.

At least 19 recordsLinked to original sources

PubMed2002

Treatment of refractory antibody mediated autoimmune disorders with an anti-CD20 monoclonal antibody (rituximab).

BACKGROUND: Rituximab, a chimeric monoclonal anti-CD20 antibody, has recently been used for the treatment of refractory antibody mediated autoimmune diseases such as immune mediated thrombocytopenia and haemolytic anaemia. PATIENTS: Because of its novel mechanism of action, rituximab was used to treat three patients with refractory systemic antibody mediated autoimmune disorders. The first patient, a 71 year old woman with idiopathic type II mixed essential cryoglobulinaemia, had both dermatological and neurological manifestations with marked renal disease attributed to her cryoglobulinaemia. Patient 2, a 73 year old woman with Goodpasture's syndrome, was refractory to conventional treatment (cyclophosphamide, prednisone, plasmapheresis). She had persistent haemoptysis and haematuria and positive antiglomerular basement membrane antibodies. The third patient, a 75 year old man with primary biliary cirrhosis, myelodysplasia, and systemic immune complex vasculitis, had progressive renal insufficiency, a macular erythematous rash, and severe thrombocytopenia. RESULTS: Treatment with rituximab resolved all clinical and laboratory manifestations in the three patients. CONCLUSIONS: Rituximab may be an important therapeutic agent for the treatment of patients refractory or intolerant to corticosteroid or cytotoxic treatment, or both.

Aged↗

PubMed2001

Deficiency of the specific granule proteins, R-binder/transcobalamin I and lactoferrin, in plasma and saliva: a new disorder.

The mechanisms of hereditary deficiency of R binder, which originates in neutrophils and exocrine gland epithelium, are unknown and may be multiple. This led us to examine if defective R binder synthesis also involves proteins that colocalize with it in neutrophil-specific granules and exocrine epithelial cells and may be under common regulatory control. Stored plasma and saliva samples from five unrelated R binder-deficient patients and control subjects were assayed for R binder, lactoferrin, cationic antimicrobial protein-18, neutrophil gelatinase-associated lipocalin, gelatinase, lysozyme, and myeloperoxidase. One patient, patient A, had lactoferrin levels below the limits of detection in both plasma and saliva in addition to his R binder deficiency. Although his deficiency involved lactoferrin as well, he had no history of predisposition to infection. PCR amplification of his R binder gene promoter region and the beginning of the first exon revealed no DNA abnormalities. His son and the son of his equally deficient brother, both presumptive heterozygotes, had mild deficiency of both R binder and lactoferrin. The results show that R binder deficiency exists in at least two forms. One, presumably the less common of the two forms, is the new hereditary entity described here, which is characterized by deficiency of more than one specific granule protein in both plasma and saliva. Despite this more widely distributed absence of the proteins than is found in congenital specific granule deficiency, infection posed no clinical problem in the affected patient.

Female↗

PubMed2001

Acquired bleeding disorder in a patient with malignant lymphoma: antibody-mediated prothrombin deficiency.

BACKGROUND: Bleeding manifestations secondary to acquired hemostatic abnormalities in cancer patients have been well described. Bleeding due to the development of hemostatic inhibitors is observed less frequently. In this report, the authors describe a patient with a low grade lymphoma who presented with an acquired bleeding disorder and abnormal hemostatic screening tests. METHODS: Patient plasma samples were collected initially and during the course of treatment. Mixing studies and specific coagulation factor assays were performed to detect and confirm any deficiencies. Patient immunoglobulin G was isolated from plasma, and binding to prothrombin was demonstrated by immunoblot method and enzyme-linked immunosorbent assay (ELISA) techniques. RESULTS: Initial prolongations in the prothombin time and the activated partial thromboplastin time suggested a factor deficiency in the common pathway of coagulation. Factor assays confirmed that the coagulation abnormality in this patient was the result of an acquired prothrombin (factor II) deficiency. This was confirmed by an immunoassay for prothrombin antigen. Further studies demonstrated the presence of a noninhibitory antibody to prothrombin that interacted with a calcium dependent epitope. CONCLUSIONS: Successful treatment of the lymphoma resulted in clearance of the antibody and complete correction of all hemostatic abnormalities and manifestations. An acquired prothrombin deficiency has not been reported previously in association with a malignancy, and this patient represents the first such documented case.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2001

Treatment of hepatitis C related thrombocytopenia with interferon alpha.

Thrombocytopenia is a common extrahepatic manifestation of hepatitis C (HCV) infection. Treatment with steroids may be effective, but can exacerbate the viral infection. Interferon alpha (INF) has documented efficacy in the treatment of HCV, but its use in the treatment of HCV thrombocytopenia is controversial. We treated eight patients with HCV-related thrombocytopenia, who had platelet counts of fewer than 50 x 10(9)/l (range: 16 to 46 x 10(9)/L) with INF 3 MU SQ three times a week. Planned duration of treatment was 24 weeks. Five patients had no evidence of hepatic cirrhosis, three had cirrhosis, and two had palpable splenomegaly. Only three patients tolerated the full course of treatment, and all three had improvement in their platelet counts to greater than 50 x 10(9)/l. Two other patients had improvement in platelet counts to more than 50 x 10(9)/l with shorter duration of treatment (six and 16 weeks, respectively). The mean increase in platelet count in the five responders was 44 x 10(9)/lL (range: 28 to 90 x 10(9)/l). The average peak platelet count in the responders was 81 x 10(9)/l (range: 62 to 136 x 10(9)/l). Duration of response ranged from four to 18+ months, with the shortest responses observed in the two patients treated with a shorter course of INF. Response was independent of the presence of cirrhosis. Responding patients had improvement in hepatic transaminases, reduction in cryoglobulin and anticardiolipin antibodies, and HCV plasma RNA when tested. Relapse was associated with an increase in these laboratory markers of HCV infection. We conclude that INF can be an effective treatment in patients with HCV-related thrombocytopenia.

Aged↗

PubMed2000

Activated recombinant human coagulation factor VII (rFVIIa) therapy for abdominal bleeding in patients with inhibitory antibodies to factor VIII.

Eight patients with inhibitors to factor VIII (4 hemophilia A and 4 nonhemophilic) were treated with recombinant activated factor VII (rFVIIa) to control severe abdominal bleeding. The recombinant factor was supplied under an open-label, emergency-use program to patients previously unresponsive to one or more alternative therapies. Therapy with rFVIIa was administered for nine separate bleeding events; one patient was treated for two separate bleeding episodes. Patients were treated for an average of 9 days and received a mean total dose of 5.2 mg of rFVIIa for control of bleeding. Treatment was considered successful and hemostasis adequate in 7 of the 9 episodes (78%). Treatment with rFVIIa was partially successful in one other episode. Four patients in this series experienced serious adverse events; all the adverse events were considered unrelated to rFVIIa therapy. The results of this limited series indicate that rFVIIa is an effective means of managing life-threatening abdominal bleeding in individuals with hemophilia or acquired antibodies to factor VIII.

Abdomen↗

PubMed2000

Ticlopidine-induced aplastic anemia: development of chromosomal abnormalities and response to immunosuppressive therapy.

Severe aplastic anemia is a well-recognized complication of ticlopidine therapy that carries a high mortality. Therapy with colony-stimulating factors or corticosteroids has been largely ineffective in this disorder. We report a case of ticlopidine-induced aplastic anemia that was successfully treated with cyclosporine and high-dose dexamethasone. The patient rapidly responded to immunosuppressive therapy and had a normal hemogram after cessation of immunosuppression. On long-term follow-up, the patient developed a progressive macrocytic anemia. Repeat bone marrow evaluation demonstrated myelodysplasia with erythroid hypoplasia. An associated chromosomal abnormality consisting of a t(3;16) (q21; p13.3) translocation was detected. This is the first report of a chromosomal abnormality associated with ticlopidine induced marrow aplastic anemia.

Aged↗

PubMed2000

Bone marrow response in treated patients with Gaucher disease: evaluation by T1-weighted magnetic resonance images and correlation with reduction in liver and spleen volume.

PURPOSE: To determine whether T1-weighted magnetic resonance (MR) images can demonstrate response in the marrow of patients with type 1 Gaucher disease treated with enzyme replacement therapy (ERT) and to determine whether a relationship exists between liver and spleen volume reductions and visible marrow changes. PATIENTS: Forty-two patients with type 1 Gaucher disease were evaluated on at least two occasions. Thirty-two patients received ERT. Of these patients, 15 had a baseline examination prior to the initiation of ERT. The remaining 10 patients did not receive ERT. DESIGN: T1-weighted and gradient recalled echo (GRE) coronal images of the femurs and hips were obtained. Concurrently, liver and spleen volumes were determined using contiguous breath-hold axial gradient-echo images. T -weighted images of the hips and femurs were evaluated to determine change or lack of change in the yellow marrow. RESULTS: Of the 32 patients receiving ERT, 14 (44%) demonstrated increased signal on T1-weighted images suggesting an increase in the amount of yellow marrow. If only the 15 patients with a baseline examination were considered, the response rate to ERT was 67%. Using Student's t-test a highly significant correlation (P<0.005) was found between marrow response and reduction in liver and spleen volume. CONCLUSIONS: Marrow changes in patients receiving ERT can be detected by T -weighted images. This response correlated with reductions in visceral volumes (P<0.0005).

Adult↗

PubMed1999

Kinetics of factor IX activity differ from that of factor IX antigen in patients with haemophilia B receiving high-purity factor IX replacement.

Pharmacokinetic studies in haemophilia B have found in vivo recovery of FIX (FIX) to be uniformly lower than the factor VIII recovery in haemophilia A. We hypothesized that this lower recovery could result from rapid binding to high-affinity receptors on platelets and endothelium. To test this hypothesis, we evaluated the kinetics of FIX activity and protein in haemophilia B patients. Twelve patients were enrolled in a double dosing, crossover study with two high-purity FIX concentrates, AlphaNine SD and MonoNine. Subjects were given 40 U kg-1 of FIX concentrate and blood samples were taken at 15, 30, and 60 min. A second infusion of 40 U kg-1 was given after the 60 min blood sample and further blood samples removed at 15, 60, 120, and 360 min after the second dose. Patients were infused with the alternate concentrate at least 7 days later. Plasma samples were assayed for FIX activity by coagulation assay and antigen by RIA. FIX antigen in the infused concentrates was measured and quantified as microg U-1. There was no difference between the two FIX concentrates (AlphaNine vs. MonoNine) in the initial (15 min) activity (57% +/-1 19% vs. 53% +/-1 12%) and antigen (62% +/-1 16% vs. 55% +/-1 19%) recoveries. Recoveries after the second FIX dose were not statistically different than those observed after the first FIX dose. In one patient, a doubling of the initial infusion dose did not increase FIX recovery after the second FIX dose. However, the recovery of FIX antigen was significantly greater than the recovery of FIX activity and the differences became more significant in the post-15 min samples. We calculated a ratio of plasma FIX antigen to FIX activity in microg U-1. Average antigen to activity ratio increased from 5.8 +/-1 1.9 microg U-1 at 15 min to 7.1 +/-1 2.2 microg U-1 at 60 min. At 420 min the ratio increased to 9.3 +/-1 2.4 microg U-1. Although these studies failed to demonstrate a significant FIX receptor pool, they did demonstrate a phenomenon of progressive loss of biologic activity of the FIX protein after infusion of FIX concentrates.

Blood Platelets↗

PubMed1998

The factor V Leiden mutation increases the risk of venous thrombosis in patients with inflammatory bowel disease.

BACKGROUND & AIMS: Thromboembolic disease is a significant cause of morbidity and mortality in patients with inflammatory bowel disease (IBD). The aim of this study was to determine the incidence and possible association of the factor V Leiden mutation with the development of thrombosis in patients with IBD. METHODS: This retrospective study included 11 patients with IBD and arterial or venous thrombosis and 51 patients with IBD and no history of thrombosis who were matched for age, sex, ethnic/racial origin, and type of IBD (controls). The presence of the factor V Leiden mutation was determined by coagulation assay and confirmed by a polymerase chain reaction method. RESULTS: Four of 11 IBD patients (36%) with thrombosis and 2 of 51 IBD controls (4%) were heterozygotes for the factor V Leiden mutation (relative risk, 14.00; 95% confidence interval, 1.55-169.25; P = 0.009, Fisher exact test). All thrombotic events in the patients with activated protein C resistance were venous with a calculated prevalence of 50% (4 of 8 patients) and a relative risk of venous thrombosis in IBD patients with factor V Leiden of 23 (95% confidence interval, 2-294; P = 0.005). CONCLUSIONS: In patients with IBD, inheritance of the factor V Leiden mutation results in a significant increased risk of venous thrombosis.

Adolescent↗

PubMed1997

Tamoxifen-associated venous thrombosis and activated protein C resistance due to factor V Leiden.

BACKGROUND: Thromboembolic events are well recognized complications of cancers and their treatment. Tamoxifen, an antiestrogen used in the treatment of breast carcinoma and other malignancies, has been associated with thrombotic events. Activated protein C resistance due to Factor V Leiden is the most prevalent inherited prothrombotic defect in populations of European descent and has been reported as a major cofactor in the development of thrombosis in women receiving estrogens. METHODS: The authors report three patients who developed thromboembolic complications while receiving tamoxifen. These patients were studied for the presence of activated protein C resistance by coagulation assay and the presence of Factor V Leiden by molecular analysis. RESULTS: All three patients had resistance to activated protein C by coagulation assay and were determined to be heterozygous for Factor V Leiden by molecular analysis. CONCLUSIONS: The authors propose that inheritance of Factor V Leiden significantly increases the risk of thrombosis in patients who receive tamoxifen therapy. All patients prescribed tamoxifen should be carefully questioned regarding personal and family histories of thrombosis and, when indicated, screened for Factor V Leiden.

Adult↗

PubMed1996

Evaluation of a tissue factor dependent factor V assay to detect factor V Leiden: demonstration of high sensitivity and specificity for a generally applicable assay for activated protein C resistance.

Resistance to the anticoagulant effects of activated protein C (APC) is now considered the most prevalent cause of inherited thrombophilia. The great majority of patients with activated protein C resistance (APCR) have a missense mutation in the factor V molecule (factor V Leiden, FVR506Q) resulting in defective inactivation of factor Va due to a loss of an APC cleavage site. The diagnosis of APCR has been based upon the inability of APC to prolong the activated partial thromboplastin (aPTT) clotting time in subjects with APCR. However, this assay has a number of deficiencies which limit its general use. We have evaluated a newly described one-stage tissue factor dependent factor V coagulation assay for APCR in 117 patients and controls and compared the results of this assay in a blinded manner to a polymerase chain reaction (PCR) based assay for the molecular defect of factor V Leiden. 43% (50/117) of the patients studied were receiving coumadin or heparin, or had a lupus anticoagulant. The tissue factor dependent factor V assay had 100% specificity and sensitivity for factor V Leiden and successfully predicted a homozygous state in the three documented homozygotes. The PCR-based assay for factor V Leiden resulted in a single false positive assay due to a silent A to C transition at nucleotide 1692 resulting in the loss of the Mnl restriction endonuclease cleavage site. The single-stage tissue factor dependent factor V assay is a highly sensitive and generally applicable assay for APCR.

Blood Coagulation Tests↗

PubMed1995

Treatment of adult T-cell leukemia-lymphoma with a combination of interferon alfa and zidovudine.

BACKGROUND: Infection with the human T-cell lymphotropic virus type I, a retrovirus, can cause a distinctive cancer, adult T-cell leukemia-lymphoma. The median survival of patients with the acute and lymphomatous forms of the disease is short, despite the use of cytotoxic chemotherapy. METHODS: We treated 19 patients with acute or lymphomatous forms of adult T-cell leukemia-lymphoma with oral zidovudine (200 mg five times daily) and interferon alfa (Intron A, 5 to 10 million units subcutaneously each day). Seven of these patients had either relapsed after multiagent cytotoxic chemotherapy or failed to respond to that treatment. RESULTS: Major responses were achieved in 58 percent of the patients (11 of 19), including complete remission in 26 percent (5 of 19). Four patients in whom prior cytotoxic therapy had failed had major responses, two of which were complete remissions. Six patients have survived for more than 12 months, with the longest remission since the discontinuation of treatment lasting more than 59 months. CONCLUSIONS: The combination of zidovudine and interferon alfa has activity against adult T-cell leukemia-lymphoma, even in patients in whom prior cytotoxic therapy has failed. This regimen should be evaluated further for its role in the treatment of adult T-cell leukemia-lymphoma.

Adolescent↗

PubMed1995

Phase I/II clinical and pharmacokinetic evaluation of liposomal daunorubicin.

PURPOSE: Since liposomal encapsulation of anticancer drugs may enhance antitumor activity while reducing toxicity in vitro, we evaluated liposomally encapsulated daunorubucin (DaunoXome; Vestar, Inc, San Dimas, CA) for safety, pharmacokinetics, and potential efficacy in patients with AIDS-related Kaposi's sarcoma (AIDS-KS). PATIENTS AND METHODS: Forty patients with advanced AIDS-KS were accrued. Successive cohorts received DaunoXome at doses of 10, 20, 30, and 40 mg/m2 given once every 3 weeks, and 40, 50, and 60 mg/m2 given once every 2 weeks. Selected KS and solid-tumor patients underwent pharmacokinetic evaluation. RESULTS: The area under the plasma concentration curve (AUC) ranged from 16.9 micrograms.h/mL to 375.3 micrograms./mL and the alpha half-life ranged from 7.8 to 8.3 hours at 10 mg/m2 to 60 mg/m2, respectively. Both pharmacokinetic profiles were significantly better compared with free daunorubicin. DaunoXome was well tolerated with no significant alopecia, mucositis, or vomiting. Neutropenia (< 1,000/microL occurred in 17% of cycles and was severe (< 500/microL) in only 2%. Anemia and thrombocytopenia were uncommon. Other adverse events included mild to moderate fatigue, nausea, and diarrhea. Even after cumulative doses greater than 1,000 mg/m2, no significant declines in cardiac function were observed. Twenty-two patients who received 50 and 60 mg/m2 were assessable for tumor response; 12 (55%) had a partial response (PR) or clinical complete response (CR). The median survival duration in all patients was 9 months. Prognostic factors for short survival were low CD4 lymphocyte counts (P = .004) and prior anthracycline therapy (P = .02). CONCLUSION: DaunoXome has an improved pharmacokinetic profile compared with free daunorubicin, and is well tolerated. DaunoXome can be given safely at doses up to 60 mg/m2 every 2 weeks and has significant antitumor activity in patients with AIDS-KS.

Acquired Immunodeficiency Syndrome↗

PubMed1993

The metal-dependent conformational changes in factor IX associated with phospholipid binding. Studies using antibodies against a synthetic peptide and chemical modification of factor IX.

Factor IX undergoes two sequential metal-ion-dependent conformational transitions [Liebman, H.A. (1987) J. Biol. Chem. 262, 7605-7612]. The first transition is metal ion dependent, but cation nonselective. The second transition is metal ion selective for Ca(II) or Sr(II) and associated with the expression of conformational determinants necessary for phospholipid membrane binding. Using antibodies raised against a synthetic peptide containing Factor IX amino acid residues 28-46, it was demonstrated that the aromatic-amino-acid-stack domain (amino acid residues 41-46) of Factor IX is surface exposed in the metal-free conformer and internalized with the initial metal-ion-dependent conformational transition. The metal-ion-induced internalization of this region of Factor IX protects the tryptophan at position 42 from oxidation by N-bromosuccinimide. The oxidation of Factor IX tryptophan residues is associated with the rapid loss of coagulant activity, but protection of Trp42 allows for the continued expression of the Ca(II)-specific antigenic determinants on Factor IX and the retention of phospholipid binding. These results suggest that the Trp42 residue located in the aromatic amino acid stack domain of human Factor IX is internalized with the metal-ion-dependent conformational transition and is essential for the expression of the phospholipid membrane binding site on Factor IX.

Animals↗

PubMed1993

Des-gamma-carboxy (abnormal) prothrombin and hepatocellular carcinoma: a critical review.

Des-gamma-carboxyprothrombin (DCP) appears to be a useful tumor marker for the evaluation of patients with HCC. DCP is produced by the malignant hepatocyte and appears to result from an acquired posttranslational defect in the vitamin K-dependent carboxylase system. DCP production is independent of vitamin K deficiency, although pharmacological doses of vitamin K can transiently suppress DCP production in some tumors. DCP levels greater than 0.1 AU/ml (100 ng/ml) on ELISA are highly suggestive of HCC or tumor recurrence. Normalization of DCP levels correlates well with successful tumor resection and appears to be an excellent marker of tumor activity. Plasma DCP does not correlate with AFP levels. However, when used together, DCP and AFP assays increase the sensitivity to HCC in more than 85% of patients. The specificity of the DCP assay appears to be superior to that of AFP; fewer than 5% of patients with nonmalignant liver disorders have DCP levels in excess of 100 ng/ml. In patients with medium to large HCC, DCP levels do correlate with tumor size. In tumors of less than 3 cm, DCP levels are increased in only 20% of patients. However, the diagnostic threshold for the DCP assay may be improved by newer assays that can detect partially carboxylated DCP species not measured by the monoclonal antibody-based ELISA.

Biomarkers↗

PubMed1993

Didanosine in the treatment of AIDS and AIDS-related complex: a critical appraisal of the dose and frequency of administration.

In the summer of 1988, dose-finding phase 1 trials of the efficacy and safety of didanosine were begun by investigators at the National Cancer Institute (NCI), by the AIDS Clinical Trials Group (ACTG) at New York University School of Medicine and the University of Rochester School of Medicine, and by researchers at Boston City Hospital (BCH). The schedules of drug administration studied included once daily (BCH), twice daily (ACTG and NCI), and three times daily (NCI). The total daily dose studied ranged from 0.8 to 66 mg/(kg.d). Significant toxicities developed in more than half of the patients receiving doses of > or = 12 mg/(kg.d). Only 5% of patients given < 10 mg/(kg.d) developed grade 3 or 4 toxicities. Although CD4+ lymphocyte counts increased at doses as low as 1.6 mg/(kg.d), a minimal effective dose could not be determined. An analysis of data on serum levels of p24 antigen suggests that a dose of > or = 5 mg/(kg.d) is superior to lower doses in terms of activity against human immunodeficiency virus. A dose given on a once-daily schedule may exhibit less antiretroviral activity than the same dose given on a twice-daily schedule. Long-term follow-up of the phase 1 trial of the once-daily regimen at BCH has further documented the safety of didanosine given at doses of < 12 mg/(kg.d) for extended periods. A review of these studies suggests that a twice-daily schedule of didanosine administration at a daily dose of 5-10 mg/(kg.d) is safe and is associated with significant antiretroviral activity in vivo.

AIDS-Related Complex↗

PubMed1993

pol mutations conferring zidovudine and didanosine resistance with different effects in vitro yield multiply resistant human immunodeficiency virus type 1 isolates in vivo.

Specific mutations in the human immunodeficiency virus type 1 (HIV-1) pol gene that cause zidovudine (3'-azido-2',3'-dideoxythymidine; AZT) and didanosine (2',3'-dideoxyinosine; ddI) resistance were studied. The 50% inhibitory concentrations (IC50s) of nucleosides for cloned viruses containing these mutations were compared with the IC50s of the corresponding triphosphate analogs for mutant recombinant-expressed reverse transcriptases (RTs). Changes in ddATP inhibition of RNA-dependent DNA polymerase activity fully accounted for the ddI resistance of the virus caused by a Leu-74-->Val substitution in RT, including an augmentation by the AZT-selected substitutions Thr-215-->Tyr and Lys-219-->Gln in RT. In contrast, the AZT-selected substitutions studied did not cause as great a change in the IC50 of AZT-triphosphate (AZT-TP) for polymerase as they did in the IC50 of AZT for mutant virus. In addition, the mutation at codon 74 suppressed AZT resistance in the virus caused by the mutations at codons 215 and 219 but did not suppress the AZT-TP resistance of enzyme containing these same mutations in RT. The mutation at codon 74 was found in clinical isolates whether or not the patient had received AZT prior to starting ddI therapy. AZT resistance coexisted with ddI resistance following acquisition of Leu-74-->Val in three clinical isolates, indicating that the suppressive effect of Val-74 on the AZT resistance of the virus does not occur in all genetic contexts. When this suppression of AZT resistance was seen in the virus, Val-74 did not appear to cause mutually exclusive changes in AZT-TP and ddATP binding to RT in vitro. The results of the in vitro experiments and characterization of clinical isolates suggest that there are differences in the functional effects of these AZT and ddI resistance mutations.

AIDS-Related Complex↗

PubMed1992

Effects of therapy with didanosine on hematologic parameters in patients with advanced human immunodeficiency virus disease.

Myelosuppression is associated with human immunodeficiency virus (HIV) infection and may also be produced by agents used for the treatment of the disease or the treatment of its complications. Didanosine (ddl; 2',3'-dideoxyinosine) is a newer purine nucleoside that has recently become available for therapy for HIV infection. The effects of didanosine on peripheral blood counts have been retrospectively evaluated in the first 170 patients treated with this new agent in four phase I trials. Patients treated with didanosine showed statistically significant improvements in hemoglobin levels, white cell counts, and granulocyte and platelet numbers as compared with baseline values. These changes were seen with or without prior therapy with zidovudine, were somewhat more pronounced at higher doses of didanosine, and persisted for up to 1 year. Reported adverse events included peripheral neuropathy, diarrhea, and most notably, pancreatitis. It is concluded that, while some toxic side effects occur, didanosine therapy in HIV infection is associated with an amelioration of HIV-induced myelosuppression.

AIDS-Related Complex↗