Fibrosis retroperitoneal relacionada con IgG4 / IgG4-Related Retroperitoneal fibrosis

OBJETIVO: Reportar dos nuevos casos de fibrosis retroperitoneal relacionada con IgG4, patología recientemente descrita. MÉTODO: Analizamos dos casos diagnosticados en nuestro centro y revisión de la literatura.RESULTADO: La enfermedad relacionada con IgG4 es una nueva entidad que agrupa diversas patologías fibroinflamatorias hasta ahora no relacionadas entre sí. Las manifestaciones clínicas son muy variables y la presentación suele ser subaguda. El tratamiento de elección son los corticoides. En el primer caso la evolución fue favorable con corticoides y azatioprina. En cambio, el segundo caso precisó cirugía en 2 ocasiones con nefrectomía radical. El diagnostico del segundo caso se realizó 9 años desde el inicio de los síntomas tras revisión de la biopsia; en ese momento no se inicio tratamiento inmunosupresor. CONCLUSIONES: Es muy importante conocerla y diagnosticarla dada la buena respuesta al tratamiento que evita complicaciones

OBJECTIVE: To report two new cases of IgG4-related retroperitoneal fibrosis, a recently described pathology. METHODS: We analyze two cases diagnosed in our center and performed a literature review. RESULT: IgG4 related disease is a recently described entity that includes previously not related pathologies. The clinical manifestations are highly variable and its presentation is usually subacute. The treatment of choice is glucocorticoids. In our first case the outcome was favorable with corticosteroids and azathioprine. However, the second case required surgery on 2 occasions with radical nephrectomy. The diagnosis of the latter was made nine years after the onset of symptoms when the biopsy was reviewed; at that moment immunosuppressive therapy was not started. CONCLUSIONS: It is very important to know and diagnose this disease because of the good response to treatment that prevents complications

Treatment of advanced human immunodeficiency virus type 1 disease with the viral entry inhibitor PRO 542.

Viral entry inhibitors represent an emerging mode of therapy for human immunodeficiency virus type 1 (HIV-1) infection. PRO 542 (CD4-immunoglobulin G2) is a tetravalent CD4-immunoglobulin fusion protein that broadly neutralizes primary HIV-1 isolates. PRO 542 binds to the viral surface glycoprotein gp120 and blocks attachment and entry of virus into CD4(+) cells. Previously, PRO 542 demonstrated antiviral activity without significant toxicity when tested at single doses ranging to 10 mg/kg. In this study, 12 HIV-infected individuals were treated with 25-mg/kg single-dose PRO 542 and then monitored for safety, antiviral effects, and PRO 542 pharmacokinetics for 6 weeks. The study examined two treatment cohorts that differed in the extent of HIV-1 disease progression. PRO 542 at 25 mg/kg was well tolerated and demonstrated a serum half-life of 3 days. Statistically significant acute reductions in HIV-1 RNA levels were observed across all study patients, and greater antiviral effects were observed in the cohort of patients with more advanced HIV-1 disease. In advanced disease (HIV-1 RNA > 100,000 copies/ml; CD4 lymphocytes < 200 cells/mm(3)), PRO 542 mediated an 80% response rate and statistically significant approximately 0.5 log(10) mean reductions in viral load for 4 to 6 weeks posttreatment. Similar findings were obtained in an analysis of all (n = 11) advanced disease patients treated to date with single doses of PRO 542 ranging from 1 to 25 mg/kg. In addition, a significant correlation was observed between antiviral effects observed in vivo and viral susceptibility to PRO 542 in vitro. The findings support continued development of PRO 542 for salvage therapy of advanced HIV-1 disease.

Single-dose safety, pharmacology, and antiviral activity of the human immunodeficiency virus (HIV) type 1 entry inhibitor PRO 542 in HIV-infected adults.

PRO 542 (CD4-IgG2) is a recombinant antibody-like fusion protein wherein the Fv portions of both the heavy and light chains of human IgG2 have been replaced with the D1D2 domains of human CD4. Unlike monovalent and divalent CD4-based proteins, tetravalent PRO 542 potently neutralizes diverse primary human immunodeficiency virus (HIV) type 1 isolates. In this phase 1 study, the first evaluation of this compound in humans, HIV-infected adults were treated with a single intravenous infusion of PRO 542 at doses of 0.2-10 mg/kg. PRO 542 was well tolerated, and no dose-limiting toxicities were identified. Area under the concentration-time curve, and peak serum concentrations increased linearly with dose, and a terminal serum half-life of 3-4 days was observed. No patient developed antibodies to PRO 542. Preliminary evidence of antiviral activity was observed as reductions in both plasma HIV RNA and plasma viremia. Sustained antiviral effects may be achieved with repeat dosing with PRO 542.

Technology evaluation: PRO-542, Progenics Pharmaceuticals inc.

Progenics's rCD4-IgG2 (PRO-542) is a recombinant fusion protein, which has been developed using the company's Universal Antiviral Binding (UnAB) technology, and is in phase I/II clinical trials for the treatment of human immunodeficiency virus type I (HIV-1) infection [273391]. At the beginning of 1997, Progenics received a Phase II Small Business Innovation Research Program (SBIR) grant from the National Institute of Allergy and Infectious diseases (NIAID) to fund the development of PRO-542 [236048]. A further grant of $2.7 million was awarded in August 1998 for the clinical evaluation of PRO-542 and other anti-HIV therapies [294200]. Progenics is collaborating with the Aaron Diamond AIDS Research Center (ADARC) in New York and the Center for Disease Control and Prevention in Atlanta [178410]. In February 2000, Progenics and Genzyme Transgenics Corp signed an agreement to continue the development of a transgenic source of PRO-542. Genzyme will develop transgenic goats that produce PRO-542 in their milk in exchange for undisclosed fees and milestone payments. Genzyme will supply PRO-542 to Progenics for clinical trials with a possibility for eventual commercial supply [357291]. Following on from this, in October 2000, Progenics received an SBIR grant to fund a two-year project with Genzyme Transgenics into the development of cost-effective methods for the manufacture of PRO-542, by optimization of the production of the drug in the milk of transgenic dairy animals [385982]. In August 2000, Punk, Ziegel & Company predicted that Progenics Pharmaceuticals will become sustainably profitable in 2003 following the launch of PRO-542 and GMK (Progenics Pharmaceuticals) in 2002 [390063].

Treatment of severe cutaneous lupus erythematosus with a chimeric CD4 monoclonal antibody, cM-T412.

BACKGROUND: Monoclonal CD4 antibodies are among the most potent immunomodulatory agents in various experimental models of autoimmune disease, including murine lupus erythematosus. OBJECTIVE: The aim of this study was to evaluate the toxicity and therapeutic efficacy of a chimeric monoclonal CD4 antibody, cM-T412, in patients with cutaneous lupus erythematosus (LE). METHODS: Five patients with severe cutaneous LE lesions received intravenously a total of 275, 400, or 475 mg of cM-T412 in single doses of 20 to 50 mg during a period of 5 to 8 weeks. RESULTS: CD4 antibody treatment induced a long-lasting decrease in disease activity. It resulted in healing of LE skin lesions, a reconstituted responsiveness to conventional treatment, or both. Despite a substantial depletion of circulating CD4+ T lymphocytes, no clinical signs of immunosuppression were noted. CONCLUSION: Monoclonal CD4 antibodies should be considered as a novel treatment for the management of severe cutaneous LE.

Safety, pharmacokinetics, and antiviral response of CD4-immunoglobulin G by intravenous bolus in AIDS and AIDS-related complex.

To assess the safety, pharmacokinetics, and antiviral effects of intravenous recombinant CD4 immunoglobulin G (CD4-IgG), a 12-week Phase One study with an optional maintenance phase was performed. Twenty-two subjects with advanced human immunodeficiency virus (HIV) infection were enrolled; 15 subjects completed the initial 12 weeks. CD4-IgG doses were 30, 100, or 300 micrograms/kg weekly; 1,000 micrograms/kg once, twice, or three times per week; or 3,000 micrograms/kg twice weekly. Serum concentrations of CD4-IgG increased linearly with dose, with average peak serum concentrations of 22 micrograms/ml with 1,000 micrograms/kg. CD4-IgG was well tolerated; one patient had self-limited tachycardia and flushing associated with CD4-IgG therapy. No changes were seen in CD4 cell counts, hematologic or coagulation studies, serum chemistries, HIV p24 antigen titers, or plasma HIV titers. No subject developed anti-CD4 antibodies. HIV isolates from five patients had IC90 values that were higher than the peak concentrations of CD4-IgG achieved in those patients. Additional studies that achieve higher CD4-IgG concentrations are necessary to evaluate the antiviral activity of this compound.

Combination therapy with recombinant human soluble CD4-immunoglobulin G and zidovudine in patients with HIV infection: a phase I study.

To determine the effect of zidovudine (ZDV) on the pharmacokinetic disposition of recombinant soluble CD4 immunoglobulin G (rCD4-IgG) and to evaluate the safety and preliminary activity of concurrent administration of ZDV with rCD4-IgG, we undertook an open-label, dose-escalating, 12-week study. The regimens of intravenous rCD4-IgG and oral ZDV we used were (a) 300 micrograms/kg rCD4-IgG twice per week and 300 mg ZDV per day, (b) 300 micrograms/kg rCD4-IgG twice per week and 600 mg ZDV per day, (c) 1,000 micrograms/kg rCD4-IgG twice per week and 300 mg ZDV per day, (d) 1,000 micrograms/kg rCD4-IgG twice per week and 600 mg ZDV per day, and (e) 3,000 micrograms/kg rCD4-IgG twice per week and 300 mg ZDV per day. Subjects were recruited from three AIDS clinical trials units. Forty-one patients with HIV infection who had CD4 cell counts < or = 500 cells/mm3 and < 120 days of previous ZDV therapy participated. Pharmacokinetic interactions were assessed with the second regimen. Mean calculated peak serum rCD4-IgG concentrations were 5.47 micrograms/ml with ZDV and 8.28 micrograms/ml without ZDV, with serum half-lives of 34.2 and 32.0 h, respectively. Antibodies to rCD4-IgG were not detected. Seven episodes of severe adverse events occurred in five patients: one episode each of severe nausea, fever, or abnormal liver function tests and four episodes of severe neutropenia. Mean hemoglobin and neutrophil counts decreased, and mean platelet counts increased in all regimens, but there were no significant differences among regimens, rCD4-IgG dose, or ZDV dose.(ABSTRACT TRUNCATED AT 250 WORDS)