Safety and efficacy of a glycoPEGylated rFVIII (turoctocog alpha pegol, N8-GP) in paediatric patients with severe haemophilia A.

Turoctocog alfa pegol (N8-GP, Novo Nordisk, Bagsværd, Denmark), an extended half-life glycoPEGylated recombinant factor VIII (rFVIII), is being developed for prophylaxis and treatment of bleeds in haemophilia A patients. pathfinder™5 is a multinational, open-label, single-arm trial to assess safety, efficacy and pharmacokinetics of N8-GP in paediatric (<12 years), previously treated patients. Boys with severe haemophilia A (<1 % FVIII), no history of inhibitors and previously treated with FVIII products (>50 exposure days [ED] for patients aged 0-5 years [younger cohort]; >150 ED for patients aged 6-11 years [older cohort]) were included. For prophylaxis, N8-GP was dosed at 50-75 IU/kg twice weekly; bleeds were treated with 20-75 IU/kg. Half-life was estimated for the patients' previous FVIII product and for N8-GP. Sixty-eight patients received N8-GP; none developed inhibitors and no other concerns were identified. Median annualised bleeding rate was 1.95 (1.94 and 1.97 in the younger and older cohorts, respectively). Twenty-nine patients (42.6 %; 15 younger and 14 older children, respectively) did not report any bleeding while on N8-GP prophylaxis; 39 patients (57.4 %; 19 younger and 20 older children, respectively) reported 70 bleeds (all mild/moderate). N8-GP treatment was successful for 78.6 % of bleeds in all patients, 80.0 % in younger and 77.5 % in older patients. Most bleeds (80.0 %) were treated with ≤2 injections. Half-life ratio between N8-GP and the patients' previous FVIII product was 1.85. N8-GP was well tolerated and provided effective prophylaxis and treatment of bleeds in paediatric patients with severe haemophilia A.

Clinical efficacy of a combination of Percoll continuous density gradient and swim-up techniques for semen processing in HIV-1 serodiscordant couples.

To evaluate the clinical efficacy of a procedure comprising a combination of Percoll continuous density gradient and modified swim-up techniques for the removal of human immunodeficiency virus type 1 (HIV-1) from the semen of HIV-1 infected males, a total of 129 couples with an HIV-1 positive male partner and an HIV-1 negative female partner (serodiscordant couples) who were treated at Keio University Hospital between January 2002 and April 2012 were examined. A total of 183 ejaculates from 129 HIV-1 infected males were processed. After swim-up, we successfully collected motile sperms at a recovery rate as high as 100.0% in cases of normozoospermia (126/126 ejaculates), oligozoospermia (6/6), and asthenozoospermia (36/36). The recovery rate of oligoasthenozoospermia was 86.7% (13/15). In processed semen only four ejaculates (4/181:2.2%) showed viral nucleotide sequences consistent with those in the blood of the infected males. After using these sperms, no horizontal infections of the female patients and no vertical infections of the newborns were observed. Furthermore, no obvious adverse effects were observed in the offspring. This protocol allowed us to collect HIV-1 negative motile sperms at a high rate, even in male factor cases. We concluded that our protocol is clinically effective both for decreasing HIV-1 infections and for yielding a healthy child.

Brief Report: The Impact of Ledipasvir/Sofosbuvir on HIV-Positive and HIV-Negative Japanese Hemophilia Patients With 1, 4, and Mixed-Genotype HCV.

INTRODUCTION: Approximately 80% of patients with hemophilia who received nonheated coagulation factor concentrates in the early 1980s were infected with hepatitis C virus (HCV), and approximately 40% of them were infected with HIV. AIM: We evaluated the efficacy and safety of administering ledipasvir (LDV)/sofosbuvir (SOF) to Japanese patients with hemophilia. METHODS: Forty-three patients with hemophilia with genotype 1 or 4 HCV were treated with LDV/SOF for 12 weeks. The efficacy, safety, and results of the laboratory tests were evaluated. RESULTS: Twenty patients were coinfected with HIV and HCV. The sustained virological response (SVR) at 12 weeks after therapy was 90% in HIV-positive patients and 100% in HIV-negative patients. The efficacy of LDV/SOF was not significantly different between HIV-positive and HIV-negative patients (P = 0.12). However, the rate of SVR at 12 weeks after therapy in the patients with cirrhosis was significantly lower than that in patients without cirrhosis (P = 0.005). Overall, 20 patients (46%) had adverse events, and while the severity of most was mild to moderate, 3 were serious, including 1 death in the HIV-positive group. All patients completed treatment with no alterations in the antiretroviral regimen. No significant abnormalities in the renal function were detected in patients taking an antiretroviral regimen of tenofovir disoproxil fumarate. CONCLUSIONS: In this cohort study, LDV/SOF was effective and safe, but the SVR in patients with cirrhosis was lower than that in the noncirrhosis group. Thus, patients with hemophilia with genotype 1/4 HCV should be treated as early as possible before the onset of cirrhosis.

Clinical evaluation of glycoPEGylated recombinant FVIII: Efficacy and safety in severe haemophilia A.

Turoctocog alfa pegol (N8-GP) is a novel glycoPEGylated extended half-life recombinant factor VIII (FVIII) product developed for prophylaxis and treatment of bleeds in patients with haemophilia A, to enable higher activity levels with less frequent injections compared with standard FVIII products. This phase III (NCT01480180), multinational, open-label, non-randomised trial evaluated the safety and clinical efficacy of N8-GP when administered for treatment of bleeds and for prophylaxis, in previously treated patients aged ≥12 years with severe haemophilia A. Patients were allocated to receive N8-GP for prophylaxis or on-demand treatment for up to 1.8 years. Patients on prophylaxis were administered one dose of 50 IU/kg of N8-GP every fourth day. Bleeds were treated with doses of 20-75 IU/kg. Total exposure to N8-GP in the trial was 14,114 exposure days (159 patient-years). For the prophylaxis arm (n=175), the median annualised bleeding rate (ABR) was 1.33 (interquartile range, 0.00-4.61), the mean ABR was 3.70 (95 % confidence interval 2.94-4.66) and 70 (40 %) patients had no bleeds during the trial. Across treatment arms, 83.6 % of bleeds resolved with one injection and 95.5 % with up to two injections. N8-GP had a favourable safety profile and was well tolerated. The frequency and types of adverse events reported were as expected in this population. One patient developed inhibitory antibodies against FVIII (≥0.6 Bethesda units [BU]) after 93 N8-GP exposure days. No clinically significant safety concerns were identified and N8-GP was effective for prophylaxis and treatment of bleeds in previously treated patients.

Analysis of the Japanese subgroup in LEOPOLD II: a phase 2/3 study of BAY 81-8973, a new recombinant factor VIII product.

BAY 81-8973, a new full length recombinant FVIII product, has been developed for prophylaxis and on-demand therapy in patients with hemophilia A. LEOPOLD II was a phase 2/3 study comparing prophylaxis versus on-demand treatment with BAY 81-8973. The analysis herein evaluated the clinical profile in Japanese subjects enrolled in LEOPOLD II. The LEOPOLD II was an open-label randomized crossover study. Our analysis evaluated the efficacy using the annualized bleeding rate, safety, and pharmacokinetics in Japanese subjects with severe hemophilia A enrolled in LEOPOLD II. The median annualized bleeding rate was 59.9/year in the on-demand group and 1.9/year in the prophylaxis group for Japanese subjects. There were no study drug-related adverse events in the Japanese subjects. None of the subjects developed FVIII inhibitors. There were no apparent clinical differences in efficacy, safety, and pharmacokinetics between the Japanese and the non-Japanese subjects. Data for the Japanese subjects showed annualized bleeding rates to be remarkably lower in the prophylaxis group compared to the on-demand group and that BAY 81-8973 exhibited a good safety profile and tolerability. These results were similar for the non-Japanese subjects. The results support adoption of BAY 81-8973 for treatment of Japanese subjects with severe hemophilia A.

Long-term safety and efficacy of emicizumab in a phase 1/2 study in patients with hemophilia A with or without inhibitors.

Emicizumab (ACE910), a recombinant humanized bispecific monoclonal antibody, provides factor VIII (FVIII) cofactor bridging function to restore hemostasis in people with hemophilia A. In a phase 1 trial involving 18 Japanese patients with severe hemophilia A, once-weekly subcutaneous administration of emicizumab 0.3, 1, or 3 mg/kg (cohorts 1, 2, and 3, respectively) was well tolerated and substantially reduced annualized bleeding rates (ABRs) in the presence or absence of FVIII inhibitors. The current study represents an open-label, long-term extension of the previously reported 12-week phase 1 study, in which 16 of 18 patients continued to receive emicizumab for up to 33.3 months. Long-term emicizumab treatment was well tolerated, with no thromboembolic events reported and no neutralizing antiemicizumab antibodies developing during the course of the study. Plasma concentrations of emicizumab increased in a dose-proportional manner, with activated partial thromboplastin times remaining short. In cohorts 1, 2, and 3, respectively, median ABRs remained low at 1.4, 0.2, and 0 compared with 4.4, 0, and 0 in the 12-week study. Overall, 8 patients experienced no bleeding events (6 patients with and 2 patients without FVIII inhibitors); dose up-titration resulted in further reduction in ABRs in patients with suboptimal bleeding control; and the episodic use of clotting factors to control bleeding was reduced. In conclusion, long-term emicizumab treatment demonstrated a favorable safety profile with encouraging efficacy, irrespective of the presence of FVIII inhibitors, in patients with hemophilia A. This study was registered at www.clinicaltrials.jp as #JapicCTI-132195.

Factor VIII-Mimetic Function of Humanized Bispecific Antibody in Hemophilia A.

BACKGROUND: In patients with severe hemophilia A, standard treatment is regular prophylactic and episodic intravenous infusions of factor VIII. However, these treatments are burdensome, especially for children, and may lead to the formation of anti-factor VIII alloantibodies (factor VIII inhibitors). Emicizumab (ACE910), a humanized bispecific antibody mimicking the cofactor function of factor VIII, was developed to abate these problems. METHODS: We enrolled 18 Japanese patients with severe hemophilia A (with or without factor VIII inhibitors) in an open-label, nonrandomized, interindividual dose-escalation study of emicizumab. The patients received subcutaneous emicizumab weekly for 12 weeks at a dose of 0.3, 1.0, or 3.0 mg per kilogram of body weight (cohorts 1, 2, and 3, respectively). The end points were safety and pharmacokinetic and pharmacodynamic profiles. An additional, exploratory end point was the annualized bleeding rate, calculated as 365.25 times the number of bleeding episodes, divided by the number of days in the treatment period as compared with the 6 months before enrollment. RESULTS: Emicizumab was associated with neither serious adverse events nor clinically relevant coagulation abnormalities. Plasma concentrations of emicizumab increased in a dose-dependent manner. Activated partial-thromboplastin times remained short throughout the study. The median annualized bleeding rates in cohorts 1, 2, and 3 decreased from 32.5 to 4.4, 18.3 to 0.0, and 15.2 to 0.0, respectively. There was no bleeding in 8 of 11 patients with factor VIII inhibitors (73%) and in 5 of 7 patients without factor VIII inhibitors (71%). Episodic use of clotting factors to control bleeding was reduced. Antibodies to emicizumab did not develop. CONCLUSIONS: Once-weekly subcutaneous administration of emicizumab markedly decreased the bleeding rate in patients who had hemophilia A with or without factor VIII inhibitors. (Funded by Chugai Pharmaceutical; JapicCTI number, 121934.).

Nonacog beta pegol (N9-GP) in haemophilia B: A multinational phase III safety and efficacy extension trial (paradigm™4).

INTRODUCTION: Paradigm™4 was an international extension trial investigating the safety and efficacy of nonacog beta pegol, a recombinant glycoPEGylated factor IX (FIX) with extended half-life, in haemophilia B patients (FIX activity ≤2%; aged 13-70years) who had previously participated in phase III pivotal (paradigm™2) or surgery (paradigm™3) trials. METHODS: Patients chose to continue treatment with nonacog beta pegol in either one of two once-weekly prophylaxis arms (10IU/kg or 40IU/kg), or an on-demand arm (40IU/kg for mild/moderate bleeds; 80IU/kg for severe bleeds). The primary objective was to evaluate immunogenicity; key secondary objectives included assessing safety and haemostatic efficacy in the treatment and prevention of bleeds. RESULTS: Seventy-one patients received prophylaxis or on-demand treatment. No patient developed an inhibitor and no safety concerns were identified. The success rate for the treatment of reported bleeds was 94.6%; most (87.9%) resolved with one injection. The median annualised bleeding rate for patients on prophylaxis was 1.36 (interquartile range [IQR] 0.00-2.23) and 1.00 (IQR 0.00-2.03) for the 10 and 40IU/kg treatment arms, respectively. The mean FIX activity trough achieved for 10 and 40IU once weekly was 9.8% and 21.3%, respectively. Fourteen patients on prophylaxis underwent 23 minor surgical procedures; haemostatic perioperative outcomes for all of those evaluated were 'excellent' or 'good'. CONCLUSIONS: Nonacog beta pegol showed a favourable tolerability profile (with no safety issues identified) with good prophylactic protection and control of bleeding in previously treated adult and adolescent haemophilia B patients.

Long-acting recombinant coagulation factor IX albumin fusion protein (rIX-FP) in hemophilia B: results of a phase 3 trial.

A global phase 3 study evaluated the pharmacokinetics, efficacy, and safety of recombinant fusion protein linking coagulation factor IX with albumin (rIX-FP) in 63 previously treated male patients (12-61 years) with severe hemophilia B (factor IX [FIX] activity ≤2%). The study included 2 groups: group 1 patients received routine prophylaxis once every 7 days for 26 weeks, followed by either 7-, 10-, or 14-day prophylaxis regimen for a mean of 50, 38, or 51 weeks, respectively; group 2 patients received on-demand treatment of bleeding episodes for 26 weeks and then switched to a 7-day prophylaxis regimen for a mean of 45 weeks. The mean terminal half-life of rIX-FP was 102 hours, 4.3-fold longer than previous FIX treatment. Patients maintained a mean trough of 20 and 12 IU/dL FIX activity on prophylaxis with rIX-FP 40 IU/kg weekly and 75 IU/kg every 2 weeks, respectively. There was 100% reduction in median annualized spontaneous bleeding rate (AsBR) and 100% resolution of target joints when subjects switched from on-demand to prophylaxis treatment with rIX-FP (P< .0001). The median AsBR was 0.00 for all prophylaxis regimens. Overall, 98.6% of bleeding episodes were treated successfully, including 93.6% that were treated with a single injection. No patient developed an inhibitor, and no safety concerns were identified. These results indicate rIX-FP is safe and effective for preventing and treating bleeding episodes in patients with hemophilia B at dosing regimens of 40 IU/kg weekly and 75 IU/kg every 2 weeks. This trial was registered at www.clinicaltrials.gov as #NCT0101496274.

Short-term efficacy of the IL6 receptor antibody tocilizumab in patients with HIV-associated multicentric Castleman disease: report of two cases.

Multicentric Castleman disease (MCD) is a lymphoproliferative disorder caused by human herpesvirus 8 (HHV8) infection HIV associated MCD (HIV-MCD) presents with various clinical symptoms. Many HIV-negative MCD patients are often treated with anti-human interleukin-6 (IL6) receptor monoclonal antibodies (tocilizumab), and successful results have been reported. IL-6 plays an important role in the development of both HIV-positive and HIV-negative MCD; however, the efficacy of tocilizumab in HIV-MCD patients is unknown. We herein report the clinical and biologic courses of two HIV-MCD patients treated with tocilizumab. In both cases, a significant and rapid clinical improvement was observed after the first infusion. However, the treatment efficacy was not maintained for a long period, and relapse occurred at 15 and 22 weeks, respectively. Both patients received rituximab and subsequently achieved complete clinical remission. Our report, in addition to data presented in the literature, suggests that tocilizumab could be an initial treatment option in patients with HIV-MCD.

Phase 3 study of recombinant factor VIII Fc fusion protein in severe hemophilia A.

This phase 3 pivotal study evaluated the safety, efficacy, and pharmacokinetics of a recombinant FVIII Fc fusion protein (rFVIIIFc) for prophylaxis, treatment of acute bleeding, and perioperative hemostatic control in 165 previously treated males aged ≥12 years with severe hemophilia A. The study had 3 treatment arms: arm 1, individualized prophylaxis (25-65 IU/kg every 3-5 days, n = 118); arm 2, weekly prophylaxis (65 IU/kg, n = 24); and arm 3, episodic treatment (10-50 IU/kg, n = 23). A subgroup compared recombinant FVIII (rFVIII) and rFVIIIFc pharmacokinetics. End points included annualized bleeding rate (ABR), inhibitor development, and adverse events. The terminal half-life of rFVIIIFc (19.0 hours) was extended 1.5-fold vs rFVIII (12.4 hours; P < .001). Median ABRs observed in arms 1, 2, and 3 were 1.6, 3.6, and 33.6, respectively. In arm 1, the median weekly dose was 77.9 IU/kg; approximately 30% of subjects achieved a 5-day dosing interval (last 3 months on study). Across arms, 87.3% of bleeding episodes resolved with 1 injection. Adverse events were consistent with those expected in this population; no subjects developed inhibitors. rFVIIIFc was well-tolerated, had a prolonged half-life compared with rFVIII, and resulted in low ABRs when dosed prophylactically 1 to 2 times per week.

Elicitation of both anti HIV-1 Env humoral and cellular immunities by replicating vaccinia prime Sendai virus boost regimen and boosting by CD40Lm.

For protection from HIV-1 infection, a vaccine should elicit both humoral and cell-mediated immune responses. A novel vaccine regimen and adjuvant that induce high levels of HIV-1 Env-specific T cell and antibody (Ab) responses was developed in this study. The prime-boost regimen that used combinations of replication-competent vaccinia LC16m8Δ (m8Δ) and Sendai virus (SeV) vectors expressing HIV-1 Env efficiently produced both Env-specific CD8(+) T cells and anti-Env antibodies, including neutralizing antibodies (nAbs). These results sharply contrast with vaccine regimens that prime with an Env expressing plasmid and boost with the m8Δ or SeV vector that mainly elicited cellular immunities. Moreover, co-priming with combinations of m8Δs expressing Env or a membrane-bound human CD40 ligand mutant (CD40Lm) enhanced Env-specific CD8(+) T cell production, but not anti-Env antibody production. In contrast, priming with an m8Δ that coexpresses CD40Lm and Env elicited more anti-Env Abs with higher avidity, but did not promote T cell responses. These results suggest that the m8Δ prime/SeV boost regimen in conjunction with CD40Lm expression could be used as an immunization platform for driving both potent cellular and humoral immunities against pathogens such as HIV-1.

Studies of assisted reproduction techniques (ART) for HIV-1-discordant couples using washed sperm and the nested PCR method: a comparison of the pregnancy rates in HIV-1-discordant couples and control couples.

In this study, the efficacy and safety of assisted reproduction techniques with the sperm-washing method and nested PCR assay were evaluated in HIV-1-discordant couples, as many HIV-1-positive people of reproductive age are getting married and wish to have children safely. Twenty-seven HIV-1-discordant couples (husband, positive; wife, negative) were enrolled in this study. The spermatozoa were separated from semen samples by density gradient centrifugation and the swim-up method. HIV-1 RNA and proviral DNA were checked using nested PCR with a detection limit of one copy before fertilization and before embryo transfer. Clinical outcomes were compared with those of matched control couples. Thirty-eight cycles of in vitro fertilization or intracytoplasmic sperm injection were performed in HIV-1-discordant couples, where the pregnancy rates per embryo transfer and per couple were 60.6 and 63.0%, respectively. These rates were significantly higher than those in control couples (P<0.05). Furthermore, all of the females and babies remained HIV-1 negative throughout the study period. Our data strongly suggest that this technique will allow HIV-1-discordant couples to conceive more safely and effectively.

Progressive renal tubular dysfunction associated with long-term use of tenofovir DF.

It became evident that tenofovir DF (TDF) causes a modest and gradual decline in GFR, however, the impact of long-term use of TDF on tubular function has not been fully evaluated. In 40 patients treated with TDF and 23 patients treated with other NRTIs, urine beta(2)-microglobulin (U-BMG), percentage tubular reabsorption of phosphate (%TRP), alkaline phosphatase (ALP), serum creatinine, and calculated GFR were prospectively measured for 96 weeks. In patients receiving TDF, median U-BMG rose from 188 microg/liter at baseline to 555 microg/liter at week 96 (p = 0.02), median %TRP declined from 94% at baseline to 90% at week 96 (p = 0.002), median ALP ratio compared with baseline persistently increased from 1 to 1.278 at week 96 (p = 0.001), and serum creatinine showed significant but minimal change from 0.64 mg/dl to 0.74 mg/dl at week 96 (p = 0.02). The GFR level declined minimally but significantly in TDF-receiving patients (-17 ml/min/1.73 m(2)), whereas it did not change in other NRTI-receiving patients [+ 3 ml/min/1.73 m(2); mixed models analysis of variance (MMANOVA) p = 0.03 for overall change from baseline to week 96]. U-BMG, %TRP, ALP, or serum creatinine did not change significantly in other NRTI-receiving patients during the observation period. In five patients with marked changes in U-BMG (>10,000 microg/liter) and %TRP (<80%), both U-BMG and %TRP immediately recovered in all patients after discontinuing TDF, whereas GFR levels did not fully recover for 6 months in three patients. Prolonged treatment with TDF caused progressive renal tubular dysfunction as well as a modest decline in GFR. If U-BMG levels >10,000 microg/liter and %TRP values <80% are observed, discontinuing TDF may be beneficial.

Buoyant density and sedimentation dynamics of HIV-1 in two density-gradient media for semen processing.

OBJECTIVE: To compare buoyant density and sedimentation kinetics of human immunodeficiency virus 1 (HIV-1) in two sperm-washing media, Percoll and Pureception. DESIGN: Laboratory study. SETTING: University hospital. PATIENT(S): None. INTERVENTION(S): Buoyant density and sedimentation kinetics of HIV-1 particles (MOLT-4/LAI strain) were measured in Percoll and Pureception using isopyknic ultracentrifugation and continuous-density-gradient centrifugation. MAIN OUTCOME MEASURE(S): The HIV-1 particles were detected and semiquantified using a reverse transcription polymerase chain reaction (RT-PCR) for HIV-1 RNA. RESULT(S): Calculated buoyant density of HIV-1 was approximately 1.042 in both media in isopyknic centrifugation. However, most HIV-1 particles were found in fractions with specific gravity less than 1.04 in both media, even after 40 minutes of density-gradient centrifugation at 1,600 g. Small viral accumulations were observed at the bottom of the tube in Pureception density gradients. CONCLUSION(S): Although we found very high efficiency of HIV-1 removal using density-gradient centrifugation, a minute quantity of virus was found at the bottom of the gradient tube when Pureception was used as the medium.

Intracellular efavirenz levels in peripheral blood mononuclear cells from human immunodeficiency virus-infected individuals.

We describe a novel method for isolating plasma-free peripheral blood mononuclear cells retaining intracellular efavirenz. Quantification of efavirenz in 13 human immunodeficiency virus-infected patients by liquid chromatography-tandem mass spectrometry showed a higher correlation of intracellular levels with unbound plasma levels (accumulation ratio, 1,190) than with total plasma levels.

Increasing genetic diversity of hepatitis C virus in haemophiliacs with human immunodeficiency virus coinfection.

Patients with inherited bleeding disorders who received clotting factor concentrates before 1987 have high rates of hepatitis C virus (HCV) or HCV/human immunodeficiency virus (HIV) infection. To determine whether the persistent nature of HIV affects the genetic diversity of HCV by less selective pressure through the immunosuppression of HIV/HCV-coinfected patients, both the change of genetic diversity and selective pressure were examined in the HCV envelope genes (E1 and E2) of 325 genotype 1a subclones from eight HIV-positive and five HIV-negative patients with two time points (more than 6 years apart). To infer the genetic diversity of HCV in each patient, we used two approaches. One method was to estimate the difference of total evolutionary distances in the phylogenetic tree between the two time points, and another was to estimate the changes of genetic diversity along the time based on the coalescence theory. The two results indicate that the HIV-positive group has significantly more diverse population structure than the HIV-negative group. A comparative analysis of the synonymous and non-synonymous substitutions found that the HIV-positive group was subject to less selective pressure than the HIV-negative group. In conclusion, HIV-positive patients would have a more diversified HCV population than HIV-negative patients due to less selective pressure from the immune system.

Prediction of the efficacy of antiviral therapy for hepatitis C virus infection by an ultrasensitive RT-PCR assay.

The efficacy of interferon therapy for hepatitis C virus (HCV) infection improved remarkably. However, virologic relapse occurs in a substantial proportion of patients with virologic response (defined as an HCV RNA level below 50 IU/ml at the end-of-treatment). A highly sensitive RT-nested PCR assay capable of detecting almost a single copy of HCV RNA and a real-time RT-PCR assay to quantify HCV RNA down to 120 copies per ml were developed. The RT-nested PCR assay showed that 1 IU of HCV RNA is equivalent to 12.2 copies. For 28 patients with virologic response (12 relapsers and 16 sustained virologic responders), week-4 and end-of-treatment plasma samples were retested. At week 4, HCV RNA was detected by the RT-nested PCR and qualitative COBAS Amplicor HCV version 2.0 in 8/9 (89%) and 6/9 (67%) samples from relapsers, and in 4/16 (25%) and 2/16 (13%) samples from sustained virologic responders, respectively. End-of-treatment samples with HCV-negative by the qualitative COBAS Amplicor were positive by the present assay in 4/12 (25%) of relapsing patients and 0/16 (0%) of sustained virologic responders. The viral levels detected by the present assay in the Amplicor-negative samples were 3.5-17.3 copies/ml, which is below the detection limit of COBAS Amplicor. In conclusion, the highly sensitive RT-nested PCR assay can predict sustained virologic response at week 4 and virologic relapse at the end-of-treatment more accurately than COBAS Amplicor, suggesting its usefulness in monitoring antiviral therapy for HCV infection.

Complete removal of HIV-1 RNA and proviral DNA from semen by the swim-up method: assisted reproduction technique using spermatozoa free from HIV-1.

BACKGROUND: Use of antiretroviral drugs has reduced the mortality rate for HIV infection and many HIV-discordant couples wish to have children. It is possible for an HIV-infected man to father children without risk of HIV transmission if HIV-free spermatozoa can be obtained from his semen. METHODS: An improved swim-up method was used to collect HIV-free spermatozoa from the semen of HIV-positive males. Diluted semen was layered over a Percoll solution with a continuous density gradient of 30-98%, and then centrifuged. The bottom layer was collected by cutting the end from the tube and the sperm suspension was collected using the swim-up method. Spermatozoa were tested by nested polymerase chain reaction (PCR) for HIV-1 RNA and DNA, with a detection limit of one copy. Spermatozoa were used for assisted reproduction in 43 couples. RESULTS: HIV-1 RNA and proviral DNA were not detected by nested-PCR assay in all 73 of the collected spermatozoa samples from 52 patients. The HIV-1-negative sperm was used for in vitro fertilization in 12 couples and for intracytoplasmic sperm injection in 31 couples. No detection of HIV-1 RNA or proviral DNA in the culture medium of the fertilized eggs was confirmed again before embryo transfer. Of the 43 female partners, 20 conceived and 27 babies were born. HIV antibodies, HIV RNA and proviral DNA were negative in all of the females and babies. CONCLUSIONS: HIV-negative spermatozoa could be obtained from semen of HIV-positive men. The method involves no risk of HIV transmission to female partners and their children.