Interactions of heparin derivatives with recombinant human keratinocyte growth factor: Structural stability and bioactivity effect study.

Heparin and heparan sulfate are important glycosaminoglycans that can regulate the activities of many vital proteins, especially the fibroblast growth factor (FGF) family. Because FGF7 (KGF) has an important role in tissue repair and maintaining the integrity of the mucosal barrier, recombinant human keratinocyte growth factor (rhKGF, palifermin) has been approved for the treatment of wound healing and oral cavity. Due to heparin plays an important role in the KGF signaling pathway, a more detailed study of the drug-drug interactions (DDIs) between rhKGF and heparin at the atomic level and investigating their synergistic effect on each other in terms of biology, especially in silico, is necessary for a better understanding of DDIs. In this study, DDIs between rhKGF and low-molecular weight heparin types (LMWH) were investigated. In this regard, scrutiny of the influence of the synergistic heparin types on the structure and biostability of rhKGF is accomplished using computational methods such as molecular docking and molecular dynamic simulations (MDs). Subsequently, the motion behavior of rhKGF in interaction with LMWHs was evaluated based on eigenvectors by using principal component analysis (PCA). Also, the binding free energies of rhKGF-LMWH complexes were calculated by the molecular mechanics/Poisson-Boltzmann surface area (MM-BPSA) method. The result showed that rhKGF-idraparinux (-6.9 kcal/mol) and rhKGF-heparin (-6.0 kcal/mol) complexes had significant binding affinity as well as they had a more stable binding to rhKGF than to other LMWH during 100 ns simulation. However, in order to confirm the curative effect of these drugs, clinical trials must be done.

Production of a 135-residue long N-truncated human keratinocyte growth factor 1 in Escherichia coli.

BACKGROUND: Palifermin (trade name Kepivance®) is an amino-terminally truncated recombinant human keratinocyte growth factor 1 (KGF-1) with 140 residues that has been produced using Escherichia coli to prevent and treat oral mucositis following radiation or chemotherapy. In this study, an amino-terminally shortened KGF-1 variant with 135 residues was produced and purified in E. coli, and its cell proliferation activity was evaluated. RESULTS: We expressed soluble KGF-1 fused to thioredoxin (TRX) in the cytoplasmic fraction of E. coli to improve its production yield. However, three N-truncated forms (KGF-1 with 140, 138, and 135 residues) were observed after the removal of the TRX protein from the fusion form by cleavage of the human enterokinase light chain C112S (hEKL C112S). The shortest KGF-1 variant, with 135 residues, was expressed by fusion with TRX via the hEKL cleavage site in E. coli and purified at high purity (> 99%). Circular dichroism spectroscopy shows that purified KGF-1135 had a structure similar to that of the KGF-1140 as a random coiled form, and MCF-7 cell proliferation assays demonstrate its biological activity. CONCLUSIONS: We identified variations in N-terminus-truncated KGF-1 and selected the most stable form. Furthermore, by a simple two-step purification, highly purified KGF-1135 was obtained that showed biological activity. These results demonstrate that KGF-1135 may be considered an alternative protein to KGF-1.

In silico enhancement of the stability and activity of keratinocyte growth factor.

Keratinocyte growth factor (KGF), a member of the fibroblast growth factor (FGF) family, has been implicated in some biological processes such as cell proliferation, development and differentiation. High mitogenic activity of this protein has made it very suitable for repairing radiation-and chemotherapy-induced damages. Palifermin, which has been developed from human KGF, is clinically applied to reduce the incidence and duration of cancer therapeutic agents. However, the activity of Palifermin is limited during treatment due to its poor stability. In this study, we have improved the stability and activity of recombinant human KGF (Palifermin) using a computational mutagenesis approach. According to the KGF multiple sequence alignment among different species as well as literature-based information, we have generated several mutations using PyMOL program and evaluated their effects on the stability and activity of KGF in silico. In order to preserve the KGF activity, we did not change the predicted functional residues. Prior to mutagenesis, the 3D structure of rhKGF was predicted by Modeller v9.15 program and quantitative evaluation of predicted models were carried out using VADAR and PROSESS servers. The stability and activity of rhKGF mutants were analyzed using GROMACS molecular dynamics (MD) simulations and docking tools, respectively. The results showed that N159S (N105S in rhKGF sequence) and I172V (I118V in rhKGF) substitutions caused an increased stability and affinity of the rhKGF to Fibroblast growth factor receptor 2 (FGFR2). We will evaluate the effects of favorable mutations on the rhKGF stability and activity in vitro.

Efficacy of palifermin on oral mucositis and acute GVHD after hematopoietic stem cell transplantation (HSCT) in hematology malignancy patients: a meta-analysis of trials.

AIM OF THE STUDY: Herein, this meta-analysis study evaluated the efficacy of palifermin after HSCT on the incidence and severity of OM or aGVHD in hematologic malignancy patients in randomized clinical trials (RCTs). MATERIALS AND METHODS: To compare the efficacy of palifermin on adverse events, OM and aGVHD compared with placebo, we searched databases of PubMed/Medline, Web of Science and Cochrane Library for RCTs based on a number of criteria. RESULTS: There was no difference observed in the incidence of OM and aGVHD between two groups. The subgroup analysis didn't show significant differences in two groups for aGVHD grade 2-4 (odds ratio [OR] = 1.54, 95% confidence interval (CI): 0.70-3.39, p = 0.28), aGVHD grade 3-4 (OR = 0.97, 95% CI: 0.48-1.94, p = 0.92), OM grade 2-4 (OR = 0.76, 95% CI: 0.42-1.38, p = 0.37) and OM grade 3-4 (OR = 0.54, 95% CI: 0.25-1.15, p = 0.11], but erythema as an adverse effect in palifermin group was higher than placebo group (OR = 1.86, 95% CI: 1.10-3.15, p = 0.02]. CONCLUSIONS: This meta-analysis of six clinical trials found no statistically significant difference in OM and aGVHD grades in patients receiving 60 µg/kg/day dose of palifermin compared with those receiving a placebo. However, oral mucosal erythema was more prevalent among patients receiving palifermin than patients receiving a placebo.

The Impact of Palifermin Use on Hematopoietic Cell Transplant Outcomes in Children.

Clinical trials evaluating palifermin have enrolled few pediatric patients, precluding safety analyses in large groups of children. We compared hematopoietic cell transplantation (HCT) outcomes among pediatric patients who did or did not receive palifermin as a preventive treatment for oral mucositis. Pediatric patients and controls, matched for HCT and donor type, disease, disease status, and age, were selected from the Center for International Blood and Marrow Transplant Research database and a 1:3 matched cohort analysis was performed. Stratified Cox proportional hazards models were built and propensity score adjustments were used to compare overall and disease-free survival outcomes between palifermin-treated and untreated patients. Three controls were identified for 90% of palifermin recipients. The remaining cases were matched with 2 (8%) controls or 1 (2%) control, for a total of 210 palifermin-treated patients matched with 606 controls. Median follow-up was 31 months in cases and 36 months in controls. Fifty-seven percent of patients underwent allogeneic HCT, mostly for acute leukemia, and 43% underwent autologous HCT, mostly for solid tumors. In univariate analyses, 2-year survival and disease-free survival rates after allogeneic HCT (58% versus 66%, P = .109; 49% versus 60%, P = .06) and after autologous HCT (73% versus 77%, P = .474; 60% versus 64%, P = .637) were similar between palifermin-treated patients and matched controls. In multivariate analysis, palifermin treatment did not significantly increase the risk of mortality (relative risk [RR], 1.20; 95% confidence interval [CI], .87 to 1.66) or of relapse (RR, 1.12; 95% CI, .78 to 1.62) compared with matched controls. No significant differences in rates of acute or chronic graft-versus-host disease (GVHD) were observed between palifermin-treated patients and matched controls. Among pediatric patients undergoing HCT, overall survival, disease-free survival, neutrophil recovery, and GVHD rates were similar between palifermin-treated patients and matched controls.

Long-Term Safety Outcomes in Patients with Hematological Malignancies Undergoing Autologous Hematopoietic Stem Cell Transplantation Treated with Palifermin to Prevent Oral Mucositis.

The purpose of our study was to compare long-term safety outcomes (overall survival, disease progression, and incidence of secondary malignancies) between palifermin and placebo in the prevention of oral mucositis in patients with hematological malignancies undergoing autologous hematopoietic stem cell transplantation (HSCT). Patients were enrolled between 1997 and 2005 into 4 phase I to III studies (3 double-blind placebo-controlled and 1 open-label) conducted at 31 sites in Australia, Europe, and the United States. Survival outcomes (overall survival, progression-free survival) were compared using hazard ratios (HRs) estimated with a Cox model that included treatment group, baseline age, disease type, Eastern Cooperative Oncology Group performance status, country, and presence of prior radiotherapy as covariates. The incidence of secondary malignancies was compared with a chi-square test. A total of 672 patients were randomized into the studies (428 palifermin and 244 placebo). The median follow-up time for subjects alive at last visit was 7.9 years (range, .1 to 14.9) for palifermin and 8.8 years (range, .1 to 14.8) for placebo. Palifermin-treated patients had overall survival (HR, 1.01; 95% confidence interval [CI], .78 to 1.31; P = .921) and progression-free survival times (HR, 1.04; 95% CI, .83 to 1.31; P = .733) that were comparable with placebo-treated patients. Secondary malignancies were reported by 13% of palifermin-treated patients versus 11% of placebo patients (P = .477). Breakdown into secondary hematological malignancies (7% versus 6%) or solid tumors (6% versus 6%) did not suggest any differences between the treatment groups. After a follow-up of up to 15 years, comparable long-term safety outcomes (overall survival, progression-free survival, and incidence of secondary malignancies) were observed for palifermin- and placebo-treated patients undergoing autologous HSCT.

Safety, Pharmacokinetics, and Efficacy of Palifermin in Children and Adolescents with Acute Leukemias Undergoing Myeloablative Therapy and Allogeneic Hematopoietic Stem Cell Transplantation: A Pediatric Blood and Marrow Transplant Consortium Trial.

Currently, effective pharmacologic treatment to reduce severe oral mucositis (OM) resulting from high-dose myeloablative cytotoxic therapy in the pediatric population is not available. Palifermin has been proven to decrease the incidence and duration of severe OM in adults with hematologic malignancies undergoing hematopoietic stem cell transplantation (HSCT). In the pediatric population, however, data on palifermin treatment are limited. A phase I dose-escalation study of palifermin in pediatric patients with acute leukemias undergoing myeloablative HSCT with total body irradiation, etoposide, and cyclophosphamide was performed to determine a safe and tolerable dose and to characterize the pharmacokinetic (PK) profile and efficacy of palifermin. Twenty-seven patients in 3 age groups (1 to 2, 3 to 11, and 12 to 16 years) and 3 dose levels (40, 60, and 80 µg/kg/day) were studied. There were no deaths, dose-limiting toxicities, or treatment-related serious adverse events. Long-term safety outcomes did not differ from what would be expected in this population. PK data showed no differences between the 3 age groups. Exposure did not increase with increase in dose. The maximum severity of OM (WHO grade 4) occurred in 6 patients (22%), none of whom was in the 80-µg/kg/day dosing group. This study showed that all doses were well tolerated and a good safety profile in all 3 pediatric age groups was seen.

Successful use of palifermin following severe anaphylaxis to pegaspargase in a pediatric patient with acute lymphoblastic leukemia.

Palifermin and pegaspargase are Escherichia coli-derived drug products. Hypersensitivity reactions, including anaphylaxis, are frequently reported with pegaspargase. In high-risk acute lymphoblasic leukemia (ALL), patients undergoing allogeneic hematopoietic stem cell transplant may be treated with palifermin as a supportive care measure for mucositis prophylaxis. However, no literature exists documenting the cross-reactivity between palifermin and pegaspargase. We report a case in which a child with very high-risk ALL having experienced severe anaphylaxis with pegaspargase was later successfully treated with palifermin during stem cell transplant conditioning.

Management of Mucositis During Chemotherapy: From Pathophysiology to Pragmatic Therapeutics.

Chemotherapy-induced mucositis is a common condition caused by the breakdown of the mucosal barrier. Symptoms can include pain, vomiting and diarrhoea, which can often necessitate chemotherapy treatment breaks or dose reductions, thus compromising survival outcomes. Despite the significant impact of mucositis, there are currently limited clinically effective pharmacological therapies for the pathology. New emerging areas of research have been proposed to play key roles in the development of mucositis, providing rationale for potential new therapeutics for the prevention, treatment or management of chemotherapy-induced mucositis. This review aims to address these new areas of research and to comment on the therapeutics arising from them.

Palifermin for prevention of oral mucositis in allogeneic hematopoietic stem cell transplantation: a single-institution retrospective evaluation.

PURPOSE: The purpose of this study is to assess the impact of palifermin on oral mucositis (OM) and its sequelae in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) who were conditioned with fractionated total body irradiation (FTBI) and etoposide. METHODS: This retrospective chart review study compared the effect of palifermin on the development of OM in patients who received this agent during an allo-HSCT (n = 99) to those who did not (n = 30). The primary end points were severity and duration of OM. Secondary end points included requirements for opioids, total parenteral nutrition (TPN), and intensive oral care; incidence of infection; length of hospital stay; and overall survival. RESULTS: There was no significant difference in the incidence of all grades of OM, but incidence of severe OM was decreased in palifermin-exposed patients (34 vs 80 %, p < 0.0001). In patients who developed OM (all grades), the median duration of OM was shorter in palifermin-exposed patients (13 vs 18 days, p = 0.0001); there was no difference in the median duration of severe OM. Patients who received palifermin used less opioids and required a shorter duration of intensive oral care. There was no difference in duration of TPN, incidence of infection, length of hospital stay, and overall survival. CONCLUSIONS: Our findings demonstrated a significant benefit with the use of palifermin for allo-HSCT recipients who were conditioned with FTBI and etoposide. Palifermin can potentially improve quality of life for this patient population and reduce complications and resources used during the transplant process. A randomized clinical trial is required to confirm these results.

Pharmacoeconomic analysis of palifermin to prevent mucositis among patients undergoing autologous hematopoietic stem cell transplantation.

Trials have shown benefits of palifermin in reducing the incidence and severity of oral mucositis in patients with hematological malignancies undergoing autologous hematopoietic stem cell transplantation (HSCT) with total body irradiation (TBI)-based conditioning regimens. Similar outcome data are lacking for patients receiving non-TBI-based regimens. We performed a retrospective evaluation on the pharmacoeconomic benefit of palifermin in the setting of non-TBI-based conditioning and autologous HSCT. Between January 2002 and December 2010, 524 patients undergoing autologous HSCT for myeloma (melphalan 200 mg/m²) and lymphoma (high-dose busulfan, cyclophosphamide, and etoposide) as preparative regimen were analyzed. Use of patient-controlled analgesia (PCA) was significantly lower in the palifermin-treated groups (myeloma: 13% versus 53%, P < .001; lymphoma: 46% versus 68%, P < .001). Median total transplant charges were significantly higher in the palifermin-treated group, after controlling for inflation (myeloma: $167,820 versus $143,200, P < .001; lymphoma: $168,570 versus $148,590, P < .001). Palifermin treatment was not associated with a difference in days to neutrophil engraftment, length of stay, and overall survival and was associated with an additional cost of $5.5K (myeloma) and $14K (lymphoma) per day of PCA avoided. Future studies are suggested to evaluate the cost-effectiveness of palifermin compared with other symptomatic treatments to reduce transplant toxicity using validated measures for pain and quality of life.

A randomized trial of prophylactic palifermin on gastrointestinal toxicity after intensive induction therapy for acute myeloid leukaemia.

Gastrointestinal toxicity, including oral mucositis, is a frequent complication of intensive combination chemotherapy for acute myeloid leukaemia (AML) and contributes substantially to treatment-related mortality. We conducted a placebo-controlled randomized trial to evaluate the efficacy of palifermin (keratinocyte growth factor), given at 60 µg/kg per daily IV for 3 d before and after chemotherapy, for mucosal protection in adult patients with previously untreated AML receiving induction therapy with idarubicin, high-dose cytarabine and etoposide. Among 155 randomized patients, there was no statistically significant difference in the rate of grade 3 and 4 oral mucositis (primary study endpoint) between the two treatment arms (three in palifermin arm (4%), 8 in placebo arm (10%; P = 0·21); however, when considering the severity of oral mucositis (World Health Organization grade 0-4), there was evidence of reduced rates of higher grades of oral mucositis in the palifermin arm (P = 0·0007, test for trend). There was a statistically significantly lower rate of grades 3 and 4 gastrointestinal adverse events in the palifermin arm (21% vs. 44% in placebo arm; P = 0·003), mainly due to a reduction in severe diarrhoea (8% palifermin, 26% placebo; P = 0·01). Palifermin has activity as a mucosal protectant in AML patients receiving intensive chemotherapy. This trial is registered at ACTRN012605000095662.

Oral Mucositis Management in Children under Cancer Treatment: A Systematic Review.

Children undergoing antineoplastic treatment often present severe side effects due to the dosage and duration of treatments, with oral mucositis emerging as one of the most prevalent and painful inflammatory conditions. There is a growing body of evidence on therapeutic interventions such as cryotherapy, low-level laser therapy, and natural compounds for this condition. The aim of this systematic review was to identify and compare therapies for the management of cancer treatment-induced oral mucositis in pediatric patients. From 2655 articles obtained in initial searches, 39 articles were considered in this systematic review, after applying inclusion/exclusion criteria. Low-level laser therapy, palifermin, honey, and zinc demonstrated reductions in oral mucositis incidence, duration, severity, and pain reported by the patient. Although there are several therapies in place for the prevention and treatment of oral mucositis in children, evidence of their efficacy is still inconclusive to establish accurate clinical protocols.

Clinical applications of palifermin: amelioration of oral mucositis and other potential indications.

Mucositis is one of the most significant toxicities in cancer patients undergoing cytotoxic treatment. It can have a negative impact on both quality of life and health economics. Severe oral mucositis can contribute to hospitalization, need for narcotic analgesics, total parentral nutrition, suboptimal delivery of anti-neoplastic treatment, and morbidity and mortality. Palifermin, a recombinant derivative of human keratinocyte growth factor, is the first active agent approved by the FDA for the prevention of severe oral mucositis in patients undergoing haematopoietic stem cell transplantation (HSCT). Several studies have also shown significant reduction in the incidence, severity and/or duration of oral mucositis in other high-risk settings such as concurrent chemoradiotherapy (CT/RT) for patients with head and neck cancer, and use of mucotoxic chemotherapeutic agents such as doxorubicin in sarcoma and fluorouracil for the treatment of colorectal cancer. The reduction in mucositis has translated into amelioration of symptoms and improvement in daily functioning as measured by patient-reported outcome in multiple studies. The clinical response to palifermin appears to be related in part to epithelial proliferation and mucosal thickening. Palifermin also has other potential clinical applications including the acceleration of immune reconstitution and inhibition of graft-versus-host disease in patients undergoing HSCT, and mitigation of dysphagia in lung cancer patients treated with concurrent CT/RT. Palifermin is generally well tolerated with mild-to-moderate skin and oral adverse events. Future studies may expand the use of palifermin into other areas that would benefit from its cytoprotective and regenerative effects.

Palifermin for the protection and regeneration of epithelial tissues following injury: new findings in basic research and pre-clinical models.

Keratinocyte growth factor (KGF) is a paracrine-acting epithelial mitogen produced by cells of mesenchymal origin, that plays an important role in protecting and repairing epithelial tissues. Pre-clinical data initially demonstrated that a recombinant truncated KGF (palifermin) could reduce gastrointestinal injury and mortality resulting from a variety of toxic exposures. Furthermore, the use of palifermin in patients with hematological malignancies reduced the incidence and duration of severe oral mucositis experienced after intensive chemoradiotherapy. Based upon these findings, as well as the observation that KGF receptors are expressed in many, if not all, epithelial tissues, pre-clinical studies have been conducted to determine the efficacy of palifermin in protecting different epithelial tissues from toxic injury in an attempt to model various clinical situations in which it might prove to be of benefit in limiting tissue damage. In this article, we review these studies to provide the pre-clinical background for clinical trials that are described in the accompanying article and the rationale for additional clinical applications of palifermin.

A meta-analysis of palifermin efficacy for the management of oral mucositis in patients with solid tumours and haematological malignancy.

BACKGROUND: Palifermin, a recombinant keratinocyte growth factor promotes thickening of the mucosa, minimising severity of mucositis caused by chemotherapy and radiotherapy. OBJECTIVE: To synthesise published literature on palifermin for the management of oral mucositis, in patients receiving chemotherapy and/or radiotherapy, aiming to ascertain recommendations for practice. METHODS: Databases searched were Medline, Embase, IPA and CIANHL. A meta-analysis included randomised controlled trials (RCT) for palifermin compared to placebo or no palifermin, with the key data extracted being number of events of severe mucositis (defined by WHO criteria grade 3 or 4). RESULTS: The meta-analysis included 10 RCT. Patients were treated for solid and haematological malignancy. Analysis suggested benefit of palifermin decreasing the incidence of severe mucositis in solid tumours RR0.76 [95%CI 0.63-0.92;p = 0.004], haematological malignancy RR0.63 [95 %CI 0.48-0.82;p = 0.0007] and overall RR0.69 [95 %CI 0.59-0.81;p < 0.0001]. CONCLUSION: Palifermin reduces the incidence of severe mucositis up to 30 % in patients receiving treatment with chemotherapy and/or radiotherapy.

A Prospective Cohort Study Comparing Long-Term Outcomes with and without Palifermin in Patients Receiving Hematopoietic Cell Transplantation for Hematologic Malignancies.

The incidence of debilitating oral mucositis (OM) can be as high as 99% after myeloablative conditioning regimens preparing patients with hematologic malignancies for hematopoietic cell transplantation (HCT). Palifermin (KGF) is a recombinant human keratinocyte growth factor that reduces the incidence and duration of severe OM. The long-term safety of KGF has not been well established, however. In this long-term prospective matched-cohort study, patients who received KGF (cases) and underwent autologous or allogeneic HCT for hematologic malignancies between 2006 and 2013 were matched 1:1 to patients who did not receive KGF (controls). The primary outcome was overall survival (OS). Other outcomes were disease relapse, new malignancies, pancreatitis, renal failure requiring dialysis, pulmonary complications, cataract surgery, and acute and chronic graft-versus-host disease (GVHD). The analysis population comprised 2191 matched pairs with a wide range of diseases and donor types that received diverse conditioning and GVHD preventive regimens, representing contemporary practice patterns. The median duration of follow-up was 8 years (range, 1 to 12.5 years). In multivariate analyses, the probabilities of OS (relative risk [RR], 1.01; 95% confidence interval [CI], 0.91 to 1.12), relapse (RR, 1.06; 95% CI, 0.94 to 1.18), new malignancies (RR, 0.89; 95% CI, 0.67 to 1.18), and cataract surgery (RR, 1.05; 95% CI, 0.74 to 1.50) were not statistically significantly different between cases and controls. In univariate analyses, no increased risks were observed for renal failure requiring dialysis, pancreatitis, acute GVHD, chronic GVHD, interstitial pneumonitis/acute respiratory distress syndrome/idiopathic pneumonia syndrome, or bronchiolitis obliterans/cryptogenic organizing pneumonia/bronchiolitis obliterans organizing pneumonia among cases compared with controls. This long-term prospective safety cohort study demonstrates that the KGF group had no increased risk of overall mortality, relapse, new malignancies, or any other key outcome. The broad inclusion criteria allow the results to be generalized to contemporary practice for patients with a wide range of diseases and receiving a wide range of HCT conditioning regimens and graft sources from diverse donor types.

Effect of Keratinocyte Growth Factor on Hospital Readmission and Regimen-Related Toxicities after Autologous Hematopoietic Cell Transplantation for Lymphoma.

Regimen-related toxicities with high-dose therapy followed by hematopoietic cell rescue leads to considerable patient distress, morbidity, and high readmission rates. Palifermin is a recombinant keratinocyte growth factor that is Food and Drug Administration-approved to decrease severe oral mucositis (OM) associated with autologous hematopoietic cell transplantation (ASCT) for hematologic malignancies. We added palifermin as a supportive care measure for patients with lymphoma undergoing ASCT with BEAM conditioning. We compared patients receiving palifermin (n = 35) with historical controls (n = 38) for toxicity and readmission outcomes. The cumulative incidence of OM of any grade was 23% in the palifermin-treated patients and 42% in the control group. Patients receiving palifermin were less likely to be readmitted (57% versus 82%; P = .04), had fewer hospital readmission days (median, 4 days versus 7 days; P < .01), and had fewer total days in the hospital through day +30 after ASCT (median, 12 days versus 15 days; P = .05). Fewer patients in the palifermin group had >20 days in the hospital through day +30 (9% in the palifermin group versus 23% of controls). Adverse events associated with palifermin were mild and transient. The addition of palifermin limits severe regimen-related toxicities and decreases readmissions and duration of hospital stay. This and other measures are needed to identify comprehensive and cost-effective approaches, possibly including palifermin, to prevent severe regimen-related toxicities and decrease health care resource utilization.

In silico mutagenesis in recombinant human keratinocyte growth factor: Improvement of stability and activity in addition to decrement immunogenicity.

The recombinant human keratinocyte growth factor (rhKGF) is clinically applied to decrease the incidence and duration of cancer therapeutic agents. Particularly, it is extensively used for oral mucositis after chemotherapy-induced damage of different human cancers. However, the usage of rhKGF in treatment is limited owing to its short half-life, poor stability, immunogenicity, tendency to aggregate, and side effects. Therefore, there is a need to enhance the stability and to reduce immunogenicity of rhKGF for therapeutic applications. In this study, the stability, activity, and immunogenicity of rhKGF were improved using computational methods. The several mutations were generated based on sequence alignment, amino acids physic-chemical properties, and the structure simulation. The 3D structure of rhKGF and proposed mutants were predicted by Modeller v9.15 program, and then were evaluated using PROSESS, PROCHECK, and ProSA web tools. Afterwards, the effect of these mutants on rhKGF structure, stability, activity, and its interaction with fibroblast growth factor receptor2-IIb (FGFR2-IIb) was analyzed through utilizing GROMACS molecular dynamics simulations and docking tools, respectively. Also, binding free energies were calculated by the Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA) method. We found that F63Y, R121K, and combine1 (K38R, F63Y, K72E, N105S) mutants lead to reduction of the number of T-cell epitopes. However, all of the selected mutants, except for R121K, could considerably increase stability and affinity of the rhKGF to FGFR2-IIb, in silico. In conclusion, this study, for the first time, offered that the combine1 and F63Y mutants could highly improve the stability and activity of rhKGF and even reduce immunogenicity without having any significant effect on the biological functions of rhKGF.

Impact of Palifermin on Transplant Outcomes in Children and Adolescents Undergoing Allogeneic Hematopoietic Cell Transplantation.

BACKGROUND: Oral mucositis (OM) is considered to be one of the worst and most debilitating complications of conditioning for hematopoietic cell transplantation (HCT). Prevention and treatment of this complication is one of the utmost priorities of supportive therapy during transplant procedure. The objective of this study was the analysis of the influence of palifermin, keratinocyte growth factor (KGF), on transplant outcomes in patients undergoing allo-HCT. PATIENTS AND METHODS: A total of 253 allo-HCTs performed between 2003-2018 in patients aged 0-19 years at a single center were analyzed. KGF was administered in 161 HCTs. Uni- and multivariate risk factor analyses were performed. RESULTS: In spite of reducing the duration and grade of mucositis, no prognostic impact of KGF was shown for overall survival, event-free survival, relapse incidence, acute and chronic graft-versus-host disease (GVHD), nor GVHD-free relapse-free survival. CONCLUSION: Palifermin had no impact on transplant outcomes in children and adolescents undergoing allo-HCT.