Safety and Efficacy Study of Intravenous Immunoglobulin to Treat Japanese Encephalitis
Condition: Japanese Encephalitis
MeSH terms: Encephalitis, Japanese; Encephalitis
Study type: Interventional
Phase: Phase 2

Summary: 
      Japanese encephalitis is caused by a viral infection of the brain transmitted by the bite of
      an infected mosquito. Patients with Japanese encephalitis can rapidly develop worsening
      conscious level and seizures. Around a third will die from the infection and half of
      survivors have serious long-term neurological disability. The majority of those affected are
      children. There are many causes of viral encephalitis, however Japanese encephalitis virus is
      the most common cause worldwide with over 60,000 cases annually. It occurs over much of Asia
      and the geographical range is expanding. There is no specific treatment for Japanese
      encephalitis virus, although several have been trialed. In this study we examined the effect
      of a new treatment, called intravenous immunoglobulin, on children with Japanese encephalitis
      in Nepal. Prior studies have suggested intravenous immunoglobulin may neutralize Japanese
      encephalitis virus and suppress damaging inflammation in the brain. It has previously been
      used in individual cases but never examined in a randomized trial. There was recently a trial
      of IVIG in West Nile encephalitis in the United States, in which Professor Solomon was on the
      Scientific Advisory Committee. In this study we will look if intravenous immunoglobulin is
      safe in this context, and that this treatment may alter the way the immune system manages the
      infection. Therefore, in this pilot study we will test the hypothesis that IVIG can be safely
      given to children with suspected JE, with no increased risk of serious adverse events
      compared with placebo. The aim of this proposal is to conduct a pilot safety and tolerability
      randomized placebo controlled trial of intravenous immunoglobulin (IVIG) in patients with
      Japanese encephalitis, to explore the relationship between JEV viral load, pro-inflammatory
      markers called cytokines and blood brain barrier markers, and the effect of IVIG on these
      relationships.
    

Detailed description: 
      Japanese encephalitis (JE) is the most important epidemic encephalitis worldwide, causing
      approximately 35-50,000 cases and 10-15,000 deaths annually. Half of the survivors have
      severe neuropsychiatric sequelae, posing a large socio-economic burden on communities that
      can ill afford it. JE virus (JEV, genus flavivirus, family Flaviviridae) has a 50 nm
      lipoprotein envelope surrounding a nucleocapsid comprised of core protein and 11 KB of
      single-stranded positive-sense RNA. The genome has 5' and 3' untranslated regions (UTR), and
      a single open reading frame encoding genes for three structural proteins (core - C,
      pre-membrane - prM and envelope - E) and 7 non-structural (NS) proteins. The E protein is
      critical for viral attachment and entry into cells, and along with NS1 and NS3 is a major
      target of the immune response.

      JEV is an arthropod-borne virus (arbovirus), transmitted in an enzootic cycle between birds,
      pigs and other vertebrates by mosquitoes, especially Culex species. Almost all of the
      population in affected parts of Asia is infected by early adulthood, but only a small
      proportion (about 1 in 300) develops clinical features. These may range from a non-specific
      febrile illness to a severe meningoencephalitis, in which seizures and clinical signs of
      raised intracranial pressure are common, and carry a poor prognosis. In addition JEV causes a
      poliomyelitis-like flaccid paralysis. The distribution of the four genotypes of JEV across
      Asia was thought to explain the clinical epidemiology, but is now thought to be a reflection
      of the virus' origin in Southeast Asia, and spread from here. However subtle differences in
      the genome may be important in determining neurological presentations of flaviviruses.

      Although there are vaccines against JEV, they are not available for many of the people that
      need them, because of issues over cost and production. Progress is being made to overcome
      these difficulties, and newer vaccines are being used increasingly. In fact Nepal has been at
      the forefront of the use of a single dose of live attenuated SA14-14-2 vaccine for JE.
      However, continues to spread across Asia, and there is no treatment. Interferon-α (IFN-α),
      which is produced as part of the innate response to JEV infection, and which has antiviral
      activity against the virus, was thought to be the most promising treatment. However, a
      randomized placebo-controlled trial showed recombinant IFN-α2a at 10 million units/m2/day did
      not improve the outcome. The pathogenesis of JE is incompletely understood, but by comparison
      with other positive sense RNA viral encephalitides, is likely to involve a mixture of viral
      cytopathology and immunopathology .The role of steroids in JEV has been examined in one
      randomized-placebo controlled trial in Thailand, which failed to show any benefit.

      IVIG currently offers one of the best possibilities for improving the outcome in JE. It has
      been used presumptively in patients with flavivirus encephalitis, including JE, and is
      postulated to act in two ways: IVIG produced in countries where flaviviruses are endemic
      contains high titers of specific neutralizing antibody, because most of the population have
      been exposed to the virus, and thus have antibodies. In addition IVIG has non-specific
      anti-inflammatory properties, particularly through the suppression of pro-inflammatory
      cytokines (e.g. in Kawasaki disease). We aim to examine the role of IVIG in JE, and also look
      at its effects on pro-inflammatory cytokines.

      The role of antibody in protection against severe disease in Japanese encephalitis: The
      humoral immune response in JE has been well characterized. When disease is due to primary
      infection (i.e. when JEV is the first flavivirus with which an individual has been infected)
      a rapid and potent IgM response occurs in serum and CSF within days of infection. By day 7
      most patients have elevated titers. Attempts to isolate virus are usually negative in such
      patients. However, the failure to mount an IgM response is associated with positive virus
      isolation and a fatal outcome. Antibody to JEV probably protects the host by restricting
      viral replication during the viraemic phase, before the virus crosses the blood brain
      barrier. Evidence from other flaviviruses suggests it may also limit damage during
      established encephalitis by neutralizing extracellular virus and facilitating lysis of
      infected cells by antibody-dependent cellular cytotoxicity.

      In surviving patients immunoglobulin class switching occurs, and within 30 days most have IgG
      in the serum and CSF. Asymptomatic infection with JEV is also associated with elevated IgM in
      the serum, but not CSF. In patients with secondary infection (i.e. those who have previously
      been infected with a different flavivirus, for example dengue infection, or yellow fever
      vaccination) there is an anamnastic response to flavivirus group common antigens. This
      secondary pattern of antibody activation is characterized by an early rise in IgG with a
      subsequent slow rise in IgM.

      Inflammation in Japanese encephalitis: At autopsy in JE, the brain is usually edematous, with
      congestion of the parenchyma . Cerebellar and uncal herniation are common.
      Histopathologically JE is characterized by perivascular inflammation with recruitment of
      macrophages, neutrophils and lymphocytes. The basal ganglia and anterior horns cells of the
      spinal cord are particularly affected, providing a pathological correlate for the
      Parkinsonism, and poliomyelitis-like flaccid paralysis, which may be seen. Viral antigen is
      predominantly in neurons although microglial cells, astrocytes and vascular endothelial cells
      are also infected. When survival is prolonged beyond 7 days acellular necrotic zones are
      seen, usually in the region of small or medium sized arteries which are surrounded by edema.

      Immunopathology in Japanese encephalitis: The pathogenesis of JE is incompletely understood,
      but available evidence indicates that, as with a number of other positive sense RNA viral
      encephalitides including lymohoctyic chorio meningitis virus (LCMV) in mice Sindbis virus,
      dengue virus, yellow fever virus and West Nile virus, there is immune-mediated damage as well
      as viral cytopathology.

      Pro-inflammatory cytokine responses in Japanese encephalitis: As detailed below under
      Preliminary Studies, there is accumulating evidence that the pro-inflammatory cytokine
      response may make an important contribution to immunopathology in JE. Among cytokines
      studied, interleukin (IL)-6, IL-8 chemokine (CXC motif) ligand (CXCL-8), and tumor necrosis
      factor (TNF)- α appear to be associated with a fatal outcome. There is also new evidence on
      the importance of other cytokines and chemokines in encephalitis caused by other
      flaviviruses, particularly West Nile virus. There are several mechanisms by which the
      pro-inflammatory response may be deleterious. Recent studies have shown IL-6, which is
      produced by neurons, microglia, astrocytes and recruited macrophages in response to viral CNS
      infection, causes an increased permeability of the blood brain barrier (BBB), which leads to
      interstitial cerebral edema, and raised intracranial pressure. TNF-α is produced by
      microglia, astrocytes and macrophages. Its multiple pro-inflammatory properties include
      upregulation of class I and II MHC expression, upregulation of cellular adhesion molecules,
      increased permeability of the BBB, and upregulation of inducible nitric oxide synthase
      (iNOS), leading to the production of nitric oxide (NO). At high concentrations NO is directly
      toxic to CNS cells, causing oxidative damage, and apoptosis. Recent evidence suggests that
      the early cytokine and chemokines responses may also be important in determining whether the
      virus even gains entry across the blood brain barrier to enter the CNS. In one study of West
      Nile virus infection, mice deficient in Toll-like receptor 3(Tlr3), which recognizes viral
      double stranded RNA, were relatively resistant to lethal infection. This was associated with
      reduced cytokine production (particularly TNF-α and IL-6), and increased viral load in the
      periphery, compared to wild type mice. TNF-α receptor 1 signaling was found to be vital for
      blood brain barrier compromise upon Tlr3 stimulation by the virus. In addition to affecting
      virally-infected cells, the inflammatory response in the CNS may also damage non-infected
      cells to cause bystander cell death. The importance of the chemokine receptor CCR5, and its
      ligand CCL5 (also known as RANTES, regulated on activation, normally T cell expressed and
      secreted) in CNS inflammation caused by flaviviruses was shown recently by their prominent
      up-regulation in a mouse model of West Nile virus infection. This was associated with CNS
      infiltration of CD4+ and CD8+ T cells, Natural killer (NK)1.1+ cells and macrophages
      expressing the receptor. The significance of CCR5 in pathogenesis was established by
      mortality studies in which infection of CCR5-/- mice was rapidly and uniformly fatal.
      Importantly, our recent study (see below) found that CCL5 was also elevated in the plasma of
      humans with JE, where higher levels were associated with a fatal outcome.

      Although clinical studies in humans with JE, and parallel studies in animal models of
      flavivirus encephalitis suggest elevated pro-inflammatory cytokines appear to be important
      and associated with a bad outcome in JE, it is not clear whether control of this strong
      pro-inflammatory response will improve the outcome. We will conduct a pilot double-blind
      placebo-controlled study on safety, tolerability and immunological markers of efficacy of
      IVIG in children with JE in Nepal, followed by a larger efficacy study.

      Preliminary studies: Professor Solomon has been studying JE and related flaviviruses since
      1994. With the support of his group and collaborators, he has shown that JEV is the most
      important cause of viral encephalitis in Vietnam, as it is in most of South and Southeast
      Asia. He showed that seizures and raised intracranial pressure are common clinical
      manifestations of infection. In collaboration with colleagues in Malaysia he developed and
      field-tested a simple rapid diagnostic test for diagnosing JE in the rural settings where it
      occurs. This test was also able to distinguish JE from dengue - a related flavivirus that
      circulates in Asia. Although dengue is better known as a cause of hemorrhagic disease, Prof
      Solomon and his team showed that it is also an important cause of neurological disease. Prof
      Solomon also showed that as well as presenting with encephalitis, JEV can present with a
      poliomyelitis-like acute flaccid paralysis, which has also more recently been recognized in
      adults infected with West Nile virus. Based on in vitro and in vivo data, together with phase
      I/II studies in humans, Prof Solomon conducted a randomized placebo controlled trial of
      interferon α-2b in children with JE (the only antiviral trial ever conducted for JE). However
      the study showed that it did not improve the outcome. To begin exploring the possible
      contribution of viral genetic diversity to the clinical epidemiology of JE, Prof Solomon
      examined the molecular evolution of the virus across Asia, and showed that the virus probably
      originated in the Indonesia and Malaysia region, and evolved here into the different
      genotypes, the most recent of which subsequently spread across Asia.

      The Liverpool group has more recently begun examining inflammation in JE. A recent
      pathological study in humans and a mouse model confirms the importance of the inflammatory
      response, and suggests there may be damage to the vascular endothelium. A study of
      pro-inflammatory and anti-inflammatory cytokines in humans with JE has shown that CSF levels
      of interleukin(IL)-6, tumor necrosis factor (TNF)-α, interferon (IFN)-α and the chemokine
      CXCL8 (IL-8) were higher in patients who died than in those who survived. IFN-γ and nitric
      oxide (NO) were also detected in the CSF of fatal cases and survivors. These findings extend
      the observations of other investigators on TNF-α and CXCL8 indicating a strong
      pro-inflammatory response in JE is associated with a poor outcome. It was also shown that
      CCL5 (RANTES) is expressed in the plasma of humans with JE, and that high plasma levels are
      associated with fatal disease. Clinical data from other flavivirus encephalitides support the
      concept that inflammation may contribute to the pathogenesis. For example, immunosuppressed
      transplant patients infected with West Nile virus develop CNS disease later than
      immunocompetent patients. Cytokines do not act in isolation, and indeed the pluripotency and
      redundancy of biological response is one of their characteristic features. Recent microarray
      experiments show a wide range of molecules are upregulated in CNS inflammatory conditions. In
      addition the Liverpool group has studied the relationship between antibody responses and
      outcome. Along with other investigators, we have shown that the presence of antibody in the
      serum and CSF is associated with survival.

      JE in Nepal: Japanese encephalitis was first recorded in Nepal in 1978 and is currently
      endemic in 24 districts. Since its first appearance there have been over 26,667 cases and
      5381 deaths. The early mortality figures were quoted at up to 60%, but more recently they
      have improved to approximately 20% in those under 15 years. The morbidity is thought to be
      around 50%. As a result of concern about the disease, there was immunization against JE in
      1999 in 3 districts, this has now been extended to cover the majority of the affected
      districts. In addition the Government vaccinated around 200 000 pigs in the Terai zone in
      2001. Despite these successes there are still ongoing cases of JE. In 2006 there were 292
      confirmed cases and 1481 AES cases of unknown etiology. These figures may under represent the
      actual numbers of cases due to logistical issues, deaths before hospital admission, and
      difficulties in confirming the diagnosis of JE with paired sera and CSF samples. Recent
      serosurveillance in the animal hosts for JE in Nepal clearly shows the virus is still present
      in the wild and is likely to remain. Seroprevalence was 48% (102/212), in pigs, 27% (15/56)
      in ducks and 50% (6/12) in horses from a total of 280 sera collected from 10 districts of
      which 44% were positive overall. Hence, JE is still a major public health problem in Nepal,
      and there is a pressing need to develop better treatments. Currently IVIG is used in Nepal to
      treat a range of pediatric conditions, including Guillain-Barré syndrome, idiopathic
      thrombocytopenic purpura.

      Rationale for use of IVIG in JE: There is currently no antiviral or immunomodulatory
      treatment for JE or indeed any flavivirus encephalitis. As outlined above, the only trials
      conducted, using interferon alpha, and using dexamethasone, failed to show any benefit. Based
      on data in preclinical studies, and observational studies in humans (see below), IVIG
      currently offers the best hope for treatment, through its antiviral and anti-inflammatory
      properties.

      Established pediatric uses of IVIG: IVIG has been established as the standard treatment for a
      number of childhood immune mediated diseases including Guillain-Barré syndrome, Kawasaki's
      disease, immune thrombocytopenia and Dermatomyositis. In Kawasaki disease, T cell and B cell
      activation is down regulated by IVIG. In thrombocytopenic purpura blockade of FCγ receptors
      is thought to be important, which may result in down regulation of secretory cytokines. In
      Guillain-Barré syndrome and dermatomyositis inhibition of complement binding and prevention
      of membranolytic attack complex formation are possible mechanisms of IVIG action. In
      addition, IVIG has been employed in the treatment and prophylaxis of a number of childhood
      viral infections where the neutralizing antibodies in the IVIG were thought to be important.
      IVIG has been used to treat, and later to provide prophylaxis, for children with hypo- or
      agammaglobulinamia with chronic enteroviral meningoencephalitis. Importantly, children with
      X-linked agammaglobulinaemia and with enteroviral meningoencephalitis treated with intensive
      and prolonged IVIG therapy have achieved long-lasting clinical and viral remission (negative
      CSF viral culture and PCR). However, the patients relapsed when IVIG was tapered, indicating
      a major beneficial role of IVIG in this condition. IVIG infusion in infants and children with
      AIDS treated with zidovudine therapy has been shown to reduce the risk of serious bacterial
      infections (16.9% IVIG group vs 24.3% placebo group (relative risk, 0.60; 95 percent
      confidence interval, 0.35 to 1.04; p = 0.07). In respiratory syncytial virus (RSV) infections
      immunoglobulin therapy has been shown to be safe and generally well tolerated in a randomized
      controlled trial (RCT) involving 102 previously healthy children, though the beneficial
      effect of reducing hospitalization and intensive care unit day were marginal in children with
      severe disease. Other established indications for passive immunization with IVIG include
      parvovirus B19 infection.

      Use of IVIG in flavivirus encephalitis: There is strong evidence to suggest that JEV, like
      other neurotropic flaviviruses, may be more susceptible to antibody-mediated, rather than
      cell-mediated immune responses. For JEV, and other neurotropic flaviviruses, clearance of
      virus is not dependent on cytolytic T cell activity, in contrast to non-neurotropic viruses.
      Neurons, as terminally differentiated cells, do not express MHC-1, which would subject them
      to lysis by CD8 T cells and non-replacement. Animal data support the importance of antibody
      mediated immunity. In one study, Konishi et. al. immunized mice with plasmid DNAs encoding
      JEV proteins that induce neutralizing antibody responses or cytotoxic T lymphocyte responses,
      and then challenged with lethal intraperitoneal doses of virus. They showed that neutralizing
      antibody prevents virus dissemination from the peripheral site to the brain, and that
      antibody-mediated mechanisms of protection were more efficient than the cytotoxic T cell
      responses. These findings supported earlier work showing that anti-envelope protein
      antibodies, are the most critical protective component in a JEV challenge model, and more
      recent passive antibody transfer experiments. In vitro work in mice shows a protective role
      for IVIG given prophylactically to prevent the flavivirus causing tick borne encephalitis and
      a protective effect when used as a treatment. In work by several different groups, use of
      IVIG containing specific anti West Nile Virus antibody during the viraemic phase, before the
      virus had entered the CNS, showed a dramatic 100% survival. Similar work with Tick borne
      encephalitis had a 100% effect on survival. There are now good data that in animal models of
      flavivirus encephalitis, peripheral administration of antibody neutralizes virus even after
      it has entered the central nervous system.

      Clinical Data: Because of the of preclinical data supporting a role for antibody treatment in
      flavivirus encephalitis, antibody treatment (in the form of IVIG) has also been used on a
      compassionate basis in JE, and West Nile encephalitis. In addition IVIG is currently being
      investigated for West Nile encephalitis in a National Institutes of Health (NIH) sponsored
      randomized placebo controlled trial in the United States (for which Prof Solomon is on the
      Scientific Steering Committee).

      IVIG was used in a 49 year old traveler returning from Vietnam who presented with JE to an
      Italian hospital. IVIG has also been used to treat West Nile virus infections in five
      patients in Israel and three in the United States. IVIG was also assessed in a placebo
      controlled trial for West Nile virus infection in the United States with no serious adverse
      effects of the drug.

      Rationale for Dose: The most commonly used dose of IVIG is 2g/kg, either given as a single
      infusion, or divided as 400mg/kg for five days. In Kawasaki disease 2g/kg as a single ten
      hour infusion is well tolerated, and was shown to be the most effective regime. In
      Guillain-Barré syndrome in children and adults the drug is most often given over 5 days, and
      this is the regime that has been used in patients with flavivirus encephalitis, and will be
      used in this study.

      Drug and Intervention: Children that meet the entry criteria will be randomly assigned to
      receive IVIG, (Reliance Biophamaceuticals Pvt. Ltd.) at a dose of 400mg/kg/day for 5 days, or
      an equivalent volume of 0.9% normal saline, using an established technique for giving fluid
      treatment in a double blind manner.

      Drug Presentation: We will use Immunorel™ intravenous immunoglobulin, which is produced by
      Reliance Biophamaceuticals Pvt. Ltd., and manufactured in China and is available through the
      Yetichem Pharmacy, Sundhara, Kathmandu and Shriran Pharmacy, Maharajgunj, Kathmandu. This is
      the IVIG product currently used most often in Nepal.

      As for most other parts of Asia, the seroprevalence of JE in China is high. By age 10,
      approximately one third of children have neutralizing antibodies to JEV, and by adulthood,
      the majority of the population has been exposed. There are extensive data showing that IVIG
      from areas where flaviviruses are endemic contains significant amounts of neutralizing
      antibody. For example for IVIG from Israel contains moderate to high levels of neutralizing
      antibody to West Nile Virus. Even though West Nile virus has only circulated in the United
      States for a few years, high levels of neutralizing antibody have been found in some IVIG
      lots.

      Anti-JEV neutralizing antibody in IVIG from Asia: We have recently examined the neutralizing
      antibody titres in a range of IVIG products from India and China, using the plaque reduction
      neutralization assay (PRNT)50. In this study we found that IVIG from the UK, contained no
      antibody, and serum from a laboratory worker who had been vaccinated against JEV contained a
      small amount of neutralizing antibody. In contrast IVIG manufactured by Bharrat, Hualan,
      Sichun and Reliance companies all had neutralizing antibody titres of greater than 1 in 400,
      with Reliance having the greatest titre, at nearly 1 in 750.

      Immunorel™ is packed in clear and colorless vials and comes in 2 pack sizes, each containing
      IVIG at a dose of 0.05g/ml (ie 50mg/ml). The available vials are, 50ml (containing 2.5g), and
      100ml (5.0g).

      Children will thus receive 400mg/kg/day of IVIG which is equivalent to 8mls/kg/day of
      Immunorel™ solution, or 8ml/kg/day of 0.9% normal saline.

      Pharmacokinetics: Distribution studies have been done with a range of IVIG preparations. In a
      study of patients who developed aseptic meningitis (as a complication of the infusion), after
      receiving 2 g/kg intravenously in 2 divided doses, the serum level increases fivefold and
      then declines by 50% over the next 72 hours as extravascular redistribution took place. By
      21- 28 days, pretreatment levels were reached. The half-life was 18-32 days, and was similar
      to native immunoglobulin. In the first 48 hours after the infusion the CSF concentration
      increased 1.5 to 7-fold but returned to normal within a week. CNS penetration may be expected
      in patients with viral meningoencephalitis or even encephalomyelitis as there will be a break
      down of the blood-brain-barrier. Metabolism of IVIG takes place in the cells of the
      reticuloendothelial system where immunoglobulins and immunoglobulin complexes are broken
      down.

      Studies with Immunorel® in normal subjects showed that peak serum concentrations occur
      immediately after intravenous injection, and are dose related. Within 24 hours up to 30% of a
      dose may be removed by catabolism and distribution. Data concerning distribution suggest that
      IVIg distributes throughout intravascular (60%) and extravascular (40%) spaces. The serum
      half life of immunoglobulin ranges between 21 and 29 days.

      Reaction Associated with Intravenous Immunoglobulin: Reactions to intravenous immunoglobulin
      tend to be related to the infusion rate and are most likely to occur during the first hour of
      the infusion. We will monitor the patient's vital signs and general status regularly
      throughout the infusion. The types of reactions that have been reported include abdominal
      pain, headache, chest-tightness, facial flushing or pallor, hot sensations, dyspnoea,
      non-urticarial skin rash, itching, hypotension, nausea or vomiting. Should any of these
      reactions develop during infusion of IVIG, the infusion will be temporarily stopped until the
      patient improves clinically (5 to 10 minutes) and then cautiously recommenced at a slower
      rate. Some patients may develop delayed adverse reactions to IVIG such as nausea, vomiting,
      chest pain, rigors, dizziness or aching legs. These adverse reactions occur after the
      infusion has stopped but usually within 24 hours. True hypersensitivity reactions to IVIG
      such as urticaria, angioedema, bronchospasm or hypotension occur very rarely. Should an
      anaphylactic reaction develop after IVIG, the infusion will be stopped and treatment
      instituted with adrenaline, oxygen, antihistamine and steroids. Hemolytic anemia and
      neutropenia have been reported in rare instances in association with IVIG treatment. Mild and
      moderate elevations of serum transaminases (AST, ALT, gamma GT) have been observed in a small
      number of patients given IVIG. Such changes were transient and not associated with the
      transmission of hepatitis. Rare complications an aseptic meningitis syndrome (AMS),
      thrombophlebitis, renal dysfunction and acute renal failure have occurred in patients
      receiving IVIG. Liver and renal function will be monitored during the study.

      Reactions Associated with Immunorel™:

      i. Primary Immune Deficiency: In patients with immunodeficiency syndrome receiving IVIG at a
      monthly dose of 400 mg/kg body weight, the reactions reported have been malaise, feeling of
      faintness, fever, chills, headache, nausea, vomiting, chest tightness, dyspnoea and chest,
      back or hip pain. Mild erythema at the infusion site has also been reported in some cases.

      ii. Idiopathic Thrombocytopenic Purpura (ITP): In the treatment of adult and paediatric
      patients with ITP at a dose of 400 mg/kg body weight, the systemic reactions were observed
      only in less than 3% of the patients. The other symptoms which were all mild and transient
      include chest tightness, a sense of tachycardia and a burning sensation in the head. At a
      dose of 1000 mg/kg body weight either as a single dose or as two doses on consecutive days in
      the treatment of adult and paediatric patients with ITP. Adverse reactions have been noted
      only in less than 10% of the patients.

      iii. Bone Marrow Transplantation: At a dose of 500 mg/kg body weight 7 days and two days
      before transplant and weekly through day 90 post-transplant, adverse reactions were reported
      in less than 7% of the patients. All reactions were classified as mild which include
      headache, flushing, fever and slight back discomfort.

      iv. Renal: Increases in creatinine and blood urea nitrogen (BUN) may be seen as soon as one
      to two days after an infusion. Progression to oliguria or anuria may require dialysis. Severe
      occasional adverse events have been reported following IVIG therapy include: acute renal
      failure, acute tubular necrosis, proximal tubular nephropathy, and osmotic nephosis.
      Correction of volume depletion by using appropriate fluids prior to initiation of IVIG
      therapy is therefore essential. Measurement of blood urea nitrogen (BUN) and /or serum
      creatinine should be performed prior to initial infusion of IVIG and again at appropriate
      intervals afterwards, with monitoring of urine output.

      iv. General: Reactions to IVIG are related to the rate of infusion. Very rarely an
      anaphylactoid reactions may occur in patients with no prior history of severe allergic
      reactions to either intramuscular or intravenous immunoglobulin.

      Mutagenicity, Carcinogenicity and Impairment of Fertility: Animal reproduction studies have
      not been conducted with Gamma IV™. Hence it is not known whether IVIG can cause fetal harm
      when administered to pregnant woman or can affect the reproduction capacity.

      Interactions with Other Drugs: The interaction of IVIG with other drugs has not been
      established in appropriate studies. Passively acquired antibody can interfere with the
      response to live, attenuated vaccines. Therefore, administration of such vaccines, e.g.
      poliomyelitis or measles, will be deferred until approximately six months after IVIG
      infusion. By the same token, immunoglobulins should not be administered for at least two
      weeks after a vaccine has been given.

      Contraindications: IVIG is contraindicated in individuals who are known to have an
      anaphylactic or severe systemic response to immune Globulin (Human). Individuals with
      selective lgA deficiencies should not receive Gamma IV™, since these individuals may
      experience server reactions to the lgA which may be present.

      Safety Warnings: The product should not be used if it is turbid. Solutions which have been
      frozen should not be used. Once opened, even if only partially used, vials should be
      discarded. IVIG should be administered only intravenously as the intramuscular and
      subcutaneous routes have not been evaluated.

      Dosage and Administration: In general it is recommended that IVIG be administered by itself
      on an initial rate of 0.01 to 0.02 ml/kg body weighty/minute for 30 minutes, if well
      tolerated the rate may be gradually increased to a maximum of 0.08 ml/kg body weight/minute.
      IVIG is recommended to be given by a separate line by itself without mixing with other
      intravenous fluids or medications the patients might be receiving. IVIG is not compatible
      with saline. The dilution if required, IVIG may be diluted with 5% Dextrose in water.
    

Intervention name(s): Intravenous immunoglobulin [ImmunoRel™ (batch 20081217)]
Intervention type(s): Drug
Intervention description(s): IVIG group received 400mg/kg/day intravenous at the rate of 0.01 to 0.02 ml/kg body weight/minute for 5 days or appearance of side effect or adverse events.
Placebo group received 0.9% saline intravenous at similar rate.
Intervention MeSH terms: Immunoglobulins; Immunoglobulins, Intravenous; Antibodies; gamma-Globulins; Rho(D) Immune Globulin
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Japanese Encephalitis, Randomized Controlled Trial, intravenous immunoglobulin, safety, efficacy, Nepal