Daclizumab

Pharmacogenomics of Old and New Immunosuppressive Drugs for Precision Medicine in Kidney Transplantation

Kidney transplantation is the preferred therapeutic option for end-stage kidney disease, but, despite major therapeutic advancements, allograft rejection continues to endanger graft survival. Every patient is unique due to his or her clinical history, drug metabolism, genetic background, and epigenetics. For this reason, examples of "personalized medicine" and "precision medicine" have steadily increased in recent decades. The final target of precision medicine is to maximize drug efficacy and minimize toxicity for each individual patient. Immunosuppressive drugs, in the setting of kidney transplantation, require a precise dosage to avoid either adverse events (overdosage) or a lack of efficacy (underdosage). In this review, we will explore the knowledge regarding the pharmacogenomics of the main immunosuppressive medications currently utilized in kidney transplantation. We will focus on clinically relevant pharmacogenomic data, that is, the polymorphisms of the genes that metabolize immunosuppressive drugs.

Antibody engineering and its therapeutic applications

As a natural function, antibodies defend the host from infected cells and pathogens by recognizing their pathogenic determinants. Antibodies (Abs) gained wide acceptance with an enormous impact on human health and have predominantly captured the arena of bio-therapeutics and bio-diagnostics. The scope of Ab-based biologics is vast, and it is likely to solve many unmet clinical needs in future. The majority of attention is now devoted to developing innovative technologies for manufacturing and engineering Abs, better suited to satisfy human needs. The advent of Ab engineering technologies (AET) led to phenomenal developments leading to the generation of Abs-/Ab-derived molecules with desirable functional properties proportional to their expanding requirements. Evolution brought by AET, from the naturally occurring Ab forms to several advanced Ab formats and derivatives, was much needed as it is of great interest to the pharmaceutical industry. Thus, numerous advancements in AET have propelled success in therapeutic Ab development, along with the potential for ever-increasing improvements. Unique characteristics of Abs, such as its diversity, specificity, structural integrity and an array of possible applications, together inspire continuous innovation in the field. Overall, the AET could assist in conquer of several limitations of Abs in terms of their applicability in the field of therapeutics, diagnostics and research; AET has so far led to the production of next-generation Abs, which have revolutionized these arenas. Here in this review, we discuss the various distinguished engineering platforms for Ab development and the progress in modern therapeutics by the so-called "next-generation Abs."

Effect of donor-to-recipient HLA matching in low-immunological risk kidney transplant recipients without induction therapy on acute rejection, graft survival, infections, and surgical complications at 3 years: The road towards new recommendations

BACKGROUND

Donor-to-recipient human leukocyte antigen mismatching is considered one of the strongest determinants for graft and patient survival in kidney transplant recipients (KTR).

OBJECTIVE

This retrospective study discusses the impact of HLA matching as low immunological risk KTR without induction therapy.

MATERIAL AND METHODS

Records of 80 adult kidney transplant patients were reviewed with three years of the follow-up. All patients had panel reactive antibodies (PRA) < 20%, absence of donor-specific antibodies (DSA) and did not receive the induction therapy. These patients were divided into two groups according to their HLA matching between donor and recipient: 55 patients with ≥ 3 HLA matches (Group I; low immunogenicity) were compared to 25 patients with <3 HLA matches (Group II; high immunogenicity). The primary endpoints included the rate and severity of acute rejection (AR) episodes, graft function (creatinine level), and survival at 1, 3, 6, 12, and 36 months. Secondary endpoints include the rate and type of infections at one-year, surgical complications at one-year, and patient survival at 1, 6, 12, and 36 months after kidney transplantation. Baseline demographic characteristics were comparable between the two groups except for recipient age, donor gender, and pre-transplant dialysis time.

RESULTS

There was no significant difference observed between two groups at one-year in infection rate, the length of hospital stay, AR severity, the rate of cytomegalovirus infection, and the occurrence of delayed graft function. However, the rate of AR, the graft function upon discharge, and the rate and type of surgical complications at one-year were significantly higher in Group II (high immunogenicity). The patient and graft survival at three years, the death-censored graft survival, and the serum creatinine levels at 1, 3, 6, 12, and 36 months were similar between two groups. Two deaths occurred in each group (NS).

CONCLUSION

In our center, the donor-to-recipient HLA mismatch is not considered an immunological risk factor in low-risk kidney transplant recipients (PRA < 20% and absence of DSA).

Fungal infections following treatment with monoclonal antibodies and other immunomodulatory therapies

Tumor necrosis factor (TNF) is a proinflammatory cytokine involved in a wide range of important physiologic processes and has a pathologic role in some diseases. TNF antagonists (infliximab, adalimumab, etanercept) are effective in treating inflammatory conditions. Antilymphocyte biological agents (rituximab, alemtuzumab), integrin antagonists (natalizumab, etrolizumab and vedolizumab), interleukin (IL)-17A blockers (secukinumab, ixekizumab) and IL-2 antagonists (daclizumab, basiliximab) are widely used after transplantation and for gastroenterological, rheumatological, dermatological, neurological and hematological disorders. Given the putative role of these host defense elements against bacterial, viral and fungal agents, the risk of infection during a treatment with these antagonists is a concern. Fungal infections, both opportunistic and endemic, have been associated with these biological therapies, but the causative relationship is unclear, especially among patients with poor control of their underlying disease or who are undergoing steroid therapy. Potential recipients of these drugs should be screened for latent endemic fungal infections. Cotrimoxazole prophylaxis could be useful for preventing Pneumocystis jirovecii infection in patients over 65 years of age who are taking TNF antagonists, antilymphocyte biological agents or who have lymphopenia and are undergoing concomitant steroid therapy. As with other immunosuppressant drugs, TNF antagonists and antilymphocyte antibodies should be discontinued for patients with active infectious disease.

Severe meningo-/encephalitis after daclizumab therapy for multiple sclerosis

Background:

Daclizumab is a monoclonal antibody that binds the high-affinity interleukin-2 receptor and was approved for the treatment of relapsing multiple sclerosis. Due to severe inflammatory brain disorders, the approval was suspended in March 2018.

Objective and Methods:

This retrospective cohort study summarizes clinical, laboratory, radiological, and histological findings of seven patients who developed meningo-/encephalitis after daclizumab therapy.

Results:

Patients presented with encephalitis and/or meningitis and suffered from systemic symptoms such as fever (5/7), exanthema (5/7), or gastrointestinal symptoms (4/7). Secondary autoimmune diseases developed. Blood analysis revealed an increase in eosinophils (5/7). Six patients fulfilled the diagnostic criteria for a drug reaction with eosinophilia and systemic symptoms (DRESS). Magnetic resonance imaging (MRI) showed multiple contrast-enhancing lesions, and enhancement of the ependyma (6/7), meninges (5/7), cranial or spinal nerves (2/7), and a vasculitic pattern (3/7). Histology revealed a pronounced inflammatory infiltrate consisting of lymphocytes, plasma cells and eosinophils, and densely infiltrated vessels. Most patients showed an insufficient therapeutic response and a high disability at last follow-up (median Expanded Disability Status Scale (EDSS) 8). Two patients died.

Conclusion:

Meningoencephalitis and DRESS may occur with daclizumab therapy. This potential lethal side effect is characterized by a dysregulated immune response. Our findings underline the importance of postmarketing drug surveillance.

Management of Immunosuppression in Liver Transplantation

Liver transplantation outcomes have significantly improved over the past few decades owing largely to the introduction of effective immunosuppression medications. Further comprehension of the unique immune microenvironment of the liver has led to the development of newer molecular targeted therapeutics. Understanding the mechanism of action and adverse effect profiles of these medications is crucial for appropriate management of posttransplant patients. In this review, the author describes the immunologic response elicited by liver transplantation, chronicles the various immunosuppressant drug classes, discusses the evidence behind their use, and evaluates the management of special subpopulations of posttransplantation patients.

Monoclonal antibody therapy and renal transplantation: focus on adverse effects

A series of monoclonal antibodies (mAbs) are commonly utilized in renal transplantation as induction therapy (a period of intense immunosuppression immediately before and following the implant of the allograft), to treat steroid-resistant acute rejections, to decrease the incidence and mitigate effects of delayed graft function, and to allow immunosuppressive minimization. Additionally, in the last few years, their use has been proposed for the treatment of chronic antibody-mediated rejection, a major cause of late renal allograft loss. Although the exact mechanism of immunosuppression and allograft tolerance with any of the currently used induction agents is not completely defined, the majority of these medications are targeted against specific CD proteins on the T or B cells surface (e.g., CD3, CD25, CD52). Moreover, some of them have different mechanisms of action. In particular, eculizumab, interrupting the complement pathway, is a new promising treatment tool for acute graft complications and for post-transplant hemolytic uremic syndrome. While it is clear their utility in renal transplantation, it is also unquestionable that by using these highly potent immunosuppressive agents, the body loses much of its innate ability to mount an adequate immune response, thereby increasing the risk of severe adverse effects (e.g., infections, malignancies, haematological complications). Therefore, it is extremely important for clinicians involved in renal transplantation to know the potential side effects of monoclonal antibodies in order to plan a correct therapeutic strategy minimizing/avoiding the onset and development of severe clinical complications.

Biologic agents in islet transplantation

Islet transplantation is today an accepted modality for treating selected patients with frequent hypoglycemic events or severe glycemic lability. Despite tremendous progress in islet isolation, culture, and preservation, clinical use is still restricted to a limited subset, and lifelong immunosuppression is required. Issues surrounding limited islet revascularization and immune destruction remain. One of the major challenges is to prevent alloreactivity and recurrence of autoimmunity against β-cells. These two hurdles can be effectively reduced by immunosuppressive therapy combining induction and maintenance treatments. The introduction of highly potent and selective biologic agents has significantly reduced the frequency of acute rejection and has prolonged graft survival, while minimizing the complications of this therapeutic scheme. This review will address the most important biological agents used in islet transplantation. We provide a historical perspective of their introduction into clinical practice and their role in current clinical protocols, aiming at improved engraftment efficiency, increased long-term survival, and better overall results of clinical islet transplantation.

Production and characterization of a CD25-specific scFv-Fc antibody secreted from Pichia pastoris

Antibodies against CD25 would be novel tools for the diagnosis and treatment of adult T cell leukemia lymphoma (ATLL) and many other immune disorders. In our previous work, we successfully produced the single-chain fragment of a variable antibody against CD25, the Dmab(scFv) antibody, using Pichia pastoris. Here, we describe a novel form of an antibody against CD25, the Dmab(scFv)-Fc antibody, also produced by P. pastoris. To construct the Dmab(scFv)-Fc antibody, the Dmab(scFv) antibody was genetically fused to the Fc fragment of a human IgG1 antibody. A fusion gene encoding Dmab(scFv)-Fc antibody was cloned into the pPIC9K plasmid and expressed at high levels, 60-70 mg/l, by P. pastoris under optimized conditions. The Dmab(scFv)-Fc antibody was similar to the Dmab(scFv) antibody in its binding specificity but different in its molecular form and Fc-mediated effector functions. The Dmab(scFv)-Fc antibody and the Dmab(scFv) antibody both bound to CD25-positive MJ cells but not to CD25-negative K562 cells. The Dmab(scFv)-Fc antibody existed as a dimer whereas the Dmab(scFv) antibody was a monomer because it lacks the Fc fragment. The Dmab(scFv)-Fc antibody enhanced the antibody-dependent cellular cytotoxicity of CD25-positive cancer cells, whereas the Dmab(scFv) antibody was inactive in the antibody-dependent cellular cytotoxicity assays. In addition, compared to the Dmab(scFv) antibody, the Dmab(scFv)-Fc antibody showed stronger immunosuppressive activity in the Con A-stimulated lymphocyte proliferation system and in the mixed lymphocyte reaction system. These results demonstrate that the Dmab(scFv)-Fc antibody produced in P. pastoris is functional, and therefore it might be developed as a novel diagnostic and therapeutic tool for ATLL and other immune disorders.

Antibody induction therapy in adult kidney transplantation: A controversy continues

Antibody induction therapy is frequently used as an adjunct to the maintenance immunosuppression in adult kidney transplant recipients. Published data support antibody induction in patients with immunologic risk to reduce the incidence of acute rejection (AR) and graft loss from rejection. However, the choice of antibody remains controversial as the clinical studies were carried out on patients of different immunologic risk and in the context of varying maintenance regimens. Antibody selection should be guided by a comprehensive assessment of immunologic risk, patient comorbidities, financial burden as well as the maintenance immunosuppressives. Lymphocyte-depleting antibody (thymoglobulin, ATGAM or alemtuzumab) is usually recommended for those with high risk of rejection, although it increases the risk of infection and malignancy. For low risk patients, interleukin-2 receptor antibody (basiliximab or daclizumab) reduces the incidence of AR without much adverse effects, making its balance favorable in most patients. It should also be used in the high risk patients with other medical comorbidities that preclude usage of lymphocyte-depleting antibody safely. There are many patients with very low risk, who may be induced with intravenous steroids without any antibody, as long as combined potent immunosuppressives are kept as maintenance. In these patients, benefits with antibody induction may be too small to outweigh its adverse effects and financial cost. Rituximab can be used in desensitization protocols for ABO and/or HLA incompatible transplants. There are emerging data suggesting that alemtuzumab induction be more successful than other antibody for promoting less intensive maintenance protocols, such as steroid withdrawal, tacrolimus monotherapy or lower doses of tacrolimus and mycophenolic acid. However, the long-term efficacy and safety of these unconventional strategies remains unknown.

Induction immunosuppressive therapies in renal transplantation

PURPOSE

Induction immunosuppressive therapies for patients undergoing renal transplantation are reviewed.

SUMMARY

The goal of induction therapy is to prevent acute rejection during the early posttransplantation period by providing a high degree of immunosuppression at the time of transplantation. Induction therapy is often considered essential to optimize outcomes, particularly in patients at high risk for poor short-term outcomes. All of the induction immunosuppressive agents currently used are biological agents and are either monoclonal (muromonab-CD3, daclizumab, basiliximab, alemtuzumab) or polyclonal (antithymocyte globulin [equine] or antithymocyte globulin [rabbit]) antibodies. Although antithymocyte globulin (rabbit) is not labeled for induction therapy, it is used for this purpose more than any other agent. Basiliximab is not considered as potent an immunosuppressive agent but has a much more favorable adverse-effect profile compared with antithymocyte globulin (rabbit) and is most commonly used in patients at low risk for acute rejection. Rituximab is being studied for use as induction therapy but to date has not demonstrated any significant benefits over placebo. While head-to-head data are available comparing most induction agents, the final decision on the most appropriate induction therapy for a transplant recipient is highly dependent on preexisting medical conditions, donor characteristics, and the maintenance immunosuppressive regimen to be used.

CONCLUSION

No standard induction immunosuppressive regimen exists for patients undergoing renal transplantation. Antithymocyte globulin (rabbit) is the most commonly used agent, whereas basiliximab appears safer. The choice of regimen depends on the preferences of clinicians and institutions.

The role of anti-inflammatory agents in age-related macular degeneration (AMD) treatment

Although age-related macular degeneration (AMD) is not a classic inflammatory disease like uveitis, inflammation has been found to have an important role in disease pathogenesis and progression. Innate immunity and autoimmune components, such as complement factors, chemokines, cytokines, macrophages, and ocular microglia, are believed to be heavily involved in AMD development. Targeting these specific inflammatory molecules has recently been explored in an attempt to better understand and treat AMD. Although antivascular endothelial growth factor therapy is the first line of defence against neovascular AMD, anti-inflammatory agents such as corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDs), immunosuppressive agents (eg, methotrexate and rapamycin), and biologics (eg, infliximab, daclizumab, and complement inhibitors) may provide an adjunct or alternative mechanism to suppress the inflammatory processes driving AMD progression. Further investigation is required to evaluate the long-term safety and efficacy of these drugs for both neovascular and non-neovascular AMD.

A randomized pilot study of systemic immunosuppression in the treatment of age-related macular degeneration with choroidal neovascularization

BACKGROUND

Age-related macular degeneration remains the leading cause of irreversible blindness in the United States and the developed world. Intravitreal injections of anti–vascular endothelial growth factor (VEGF) medications have become standard of care for the treatment of the wet form of the disease. Recent reports have demonstrated an association with various immune factors. We aimed to investigate the effect of immunosuppressive therapy in the clinical course of the wet form of the disease. We compared anti-VEGF therapy plus one of three systemic immunosuppressive therapies versus anti-VEGF therapy alone for recurrent choroidal neovascularization associated with age-related macular degeneration.

METHODS

This was a pilot, Phase I/II, prospective, randomized, unmasked, single-center trial. Patients with subretinal exudation secondary to recurrent choroidal neovascularization associated with age-related macular degeneration were included in the study. Patients were randomized to 1 of 3 systemic arms immunosuppressive agents (daclizumab, rapamycin, or infliximab) for 6 months plus intraocular anti-VEGF therapy if indicated, compared with a group who received only anti-VEGF therapy if indicated.

RESULTS

The number of anti-VEGF injections per group, visual acuity, retinal thickness, and safety measures were assessed in all groups. Thirteen patients were randomized; comparing anti-VEGF injections before and during the study, a decrease in the number of injections from 0.73 injections per month to 0.42 for daclizumab and from 0.67 to 0.34 for sirolimus was seen, while no apparent decrease was seen for either infliximab or observation. Visual acuities were maintained in all groups.

CONCLUSION

These preliminary data suggest that some immunosuppressive agents given systemically can alter the clinical course of the wet form of the disease and support the notion that more definitive clinical trials of immune mediation of age-related macular degeneration are indicated.

Interleukin-2 receptor blockade with humanized monoclonal antibody for solid organ transplantation

IMPORTANCE OF THE FIELD

Induction therapy has reduced the incidence of acute rejection compared with historical standards. The potency of currently available induction immunosuppression is not without risk and should be carefully considered. Induction with daclizumab, an IL-2 receptor antagonist, has been used safely and effectively for over 10 years across different transplant types. As a result of daclizumab use, transplant centers are able to implement steroid-sparing or calcineurin minimization protocols. Unfortunately, the manufacturing costs have resulted in withdrawal of this agent from the market reducing the options for patients undergoing transplantation.

AREAS COVERED IN THIS REVIEW

This review will update the reader on recently published daclizumab studies in adult solid organ transplant recipients, focusing on comparative studies with other induction agents.

WHAT THE READER WILL GAIN

This paper will provide a summary of comparative studies between daclizumab and other induction therapies focusing on their efficacy and safety.

TAKE HOME MESSAGE

Novel applications, such as long-term use in combination with calcineurin-inhibitor dose reduction and its value in the treatment of acute or chronic rejection have yet to be explored. Since daclizumab has been withdrawn from the market, future IL-2 receptor blockade will have to be achieved with basiliximab, which is a chimeric, monoclonal antibody directed against the same epitope.

Human framework adaptation of a mouse anti-human IL-13 antibody

Humanization of a potent neutralizing mouse anti-human IL-13 antibody (m836) using a method called human framework adaptation (HFA) is reported. HFA consists of two steps: human framework selection (HFS) and specificity-determining residue optimization (SDRO). The HFS step involved generation of a library of m836 antigen binding sites combined with diverse human germline framework regions (FRs), which were selected based on structural and sequence similarities between mouse variable domains and a repertoire of human antibody germline genes. SDRO consisted of diversifying specificity-determining residues and selecting variants with improved affinity using phage display. HFS of m836 resulted in a 5-fold loss of affinity, whereas SDRO increased the affinity up to 100-fold compared to the HFS antibody. Crystal structures of Fabs in complex with IL-13 were obtained for m836, the HFS variant chosen for SDRO, and one of the highest-affinity SDRO variants. Analysis of the structures revealed that major conformational changes in FR-H1 and FR-H3 occurred after FR replacement, but none of them had an evident direct impact on residues in contact with IL-13. Instead, subtle changes affected the V(L)/V(H) (variable-light domain/variable-heavy domain) interface and were likely responsible for the 5-fold decreased affinity. After SDRO, increased affinity resulted mainly from rearrangements in hydrogen-bonding pattern at the antibody/antigen interface. Comparison with m836 putative germline genes suggested interesting analogies between natural affinity maturation and the engineering process that led to the potent HFA anti-human IL-13 antibody.

Monoclonal antibodies for podocytopathies: rationale and clinical responses

The podocytopathies, including minimal-change nephropathy, focal segmental glomerulosclerosis, collapsing glomerulopathy, and diffuse mesangial sclerosis, involve diverse types of injury to podocytes. These injuries can have genetic causes, or can be caused by viral infection, mechanical stress, medication or-probably-immunologic injury. Several lines of evidence-including the immunosuppressive effects of standard therapies-suggest a role for immunologic injury in some cases, but the precise pathologic mechanisms are far from clear. Despite this uncertainty, newly available biologic therapies that target immune cells and cytokines have been used to treat a number of patients with different podocytopathies. Of these therapies, the greatest experience has been gained with rituximab. The data on all such therapies remain too fragmentary to provide firm conclusions, but further clinical research with such agents might help to define pathogenetic pathways and could potentially contribute to new therapies.

Thrombotic microangiopathy in haematopoietic stem cell transplantation: diagnosis and treatment

Each year in the US, more than 10 000 patients benefit from allogeneic haematopoietic stem cell transplantation (HSCT), a modality that offers an excellent chance of eradicating malignancy but confers a higher risk of treatment-related mortality. An uncommon but devastating consequence of HSCT is transplantation-associated thrombotic microangiopathy (TA-TMA). The incidence of TA-TMA ranges from 0.5% to 76%, with a mortality rate of 60-90% despite treatment. Although there appears to be a consistent treatment approach to idiopathic thrombotic thrombocytopenic purpura (TTP) using plasma exchange, corticosteroids and rituximab, the treatment strategies for TA-TMA are perplexing, in part, because the literature regarding this complex condition does not provide true consensus for incidence, aetiology, diagnostic criteria, classification and optimal therapy. The classic definition of idiopathic TTP includes schistocytes on the peripheral blood smear, thrombocytopenia and increased serum lactate dehydrogenase. Classic idiopathic TTP has been attributed to deficient activity of the metalloproteinase responsible for cleaving ultra-large von Willebrand factor multimers. This protease is a member of the 'a disintegrin and metalloprotease with thrombospondin type 1 motif' family and is subsequently named ADAMTS-13. Severely deficient ADAMTS-13 activity (<5% of normal) is associated with idiopathic TTP in 33-100% of patients. In constrast to the pathophysiology of idiopathic TTP, patients with TA-TMA have >5% ADAMTS-13 serum activity. These data may explain why plasma exchange, a standard treatment modality for idiopathic TTP that restores ADAMTS-13 activity, is not effective in TA-TMA. TA-TMA has a multifactorial aetiology of endothelial damage induced by intensive conditioning therapy, irradiation, immunosuppressants, infection and graft-versus-host disease. Treatment consists of substituting calcineurin inhibitors with an alternative immunosuppressive agent that possesses another mode of action. One candidate may be daclizumab, especially in those with mild to moderate TMA. Rituximab therapy or the addition of defibrotide may also be beneficial. In general, plasma exchange is not recommended.

Human facial allotransplantation: a 2-year follow-up study

BACKGROUND

Progress in composite tissue allotransplantation could provide a new treatment for patients with severe facial disfigurements. We did a partial facial allotransplantation in 2006, and report here the 2 year follow-up of the patient.

METHODS

The recipient, a 30-year-old man from China, had his face severely injured by a bear in October, 2004. Allograft composite tissue transplantation was done in April, 2006, after careful systemic preparation. The surgery included anastomosis of the right mandibular artery and anterior facial vein, whole repair of total nose, upper lip, parotid gland, front wall of the maxillary sinus, part of the infraorbital wall, and zygomatic bone. Facial nerve anastomosis was done during the surgery. Quadruple immunomodulatory therapy was used, containing tacrolimus, mycophenolate mofetil, corticosteroids, and humanised IL-2 receptor monoclonal antibody. Follow-up included T lymphocyte subgroups in peripheral blood, pathological and immunohistochemical examinations, functional progress, and psychological support.

FINDINGS

Composite tissue flap survived well. There were three acute rejection episodes at 3, 5, and 17 months after transplantation, but these were controlled by adjustment of the tacrolimus dose or the application of methylprednisolone pulse therapy. Hepatic and renal functions were normal, and there was no infection. The patient developed hyperglycaemia on day 3 after transplantation, which was controlled by medication.

INTERPRETATION

Facial transplantation could be successful in the short term, but the procedure was not without complications. However, promising results could mean that this procedure might be an option for long-term restoration of severe facial disfigurement.