Ibrexafungerp, a Novel Triterpenoid Antifungal in Development for the Treatment of Mold Infections.

Molds are ubiquitous in the environment, and immunocompromised patients are at substantial risk of morbidity and mortality due to their underlying disease and the resistance of pathogenic molds to currently recommended antifungal therapies. This combination of weakened-host defense, with limited antifungal treatment options, and the opportunism of environmental molds renders patients at risk and especially vulnerable to invasive mold infections such as Aspergillus and members of the Order Mucorales. Currently, available antifungal drugs such as azoles and echinocandins, as well as combinations of the same, offer some degree of efficacy in the prevention and treatment of invasive mold infections, but their use is often limited by drug resistance mechanisms, toxicity, drug-drug interactions, and the relative paucity of oral treatment options. Clearly, there is a need for agents that are of a new class that provides adequate tissue penetration, can be administered orally, and have broad-spectrum efficacy against fungal infections, including those caused by invasive mold organisms. Ibrexafungerp, an orally bioavailable glucan synthase inhibitor, is the first in a new class of triterpenoid antifungals and shares a similar target to the well-established echinocandins. Ibrexafungerp has a very favorable pharmacokinetic profile for the treatment of fungal infections with excellent tissue penetration in organs targeted by molds, such as the lungs, liver, and skin. Ibrexafungerp has demonstrated in vitro activity against Aspergillus spp. as well as efficacy in animal models of invasive aspergillosis and mucormycosis. Furthermore, ibrexafungerp is approved for use in the USA for the treatment of women with vulvovaginal candidiasis. Ibrexafungerp is currently being evaluated in clinical trials as monotherapy or in combination with other antifungals for treating invasive fungal infections caused by yeasts and molds. Thus, ibrexafungerp offers promise as a new addition to the clinician's armamentarium against these difficult-to-treat infections.

The squiggle tail (squig) mutation in mice is associated with a deletion in the mesenchyme homeobox 1 (Meox1) gene.

OBJECTIVE: We have taken a positional approach to assign the spontaneous squiggle tail (squig) mutation in mice to a specific gene defect. RESULTS: A large panel of backcross mice was produced and characterized to map squig to high genetic resolution on mouse Chromosome (Chr) 11. Two overlapping candidate genes that co-localized with squig (Meox1, for mesenchyme homeobox 1; and Gm11551, which encodes a lncRNA located entirely within the first intron of Meox1) were fully sequenced to discover any squig-specific defects. This analysis revealed a 3195 bp deletion that includes all of Meox1, Exon 1 but does not disrupt Gm11551. We recommend that the squig mutation be renamed Meox1squig, and suggest that this variant may offer an appropriate animal model for Klippel-Feil syndrome 2 (KFS2) in humans.

Randomized, Double-Blind, Placebo-Controlled, Fixed-Dose Study to Evaluate the Efficacy and Safety of Amphetamine Extended-Release Tablets in Adults With Attention-Deficit/Hyperactivity Disorder.

Objective: To evaluate the efficacy and safety of amphetamine extended-release tablets (AMPH ER TAB) in adults with attention-deficit/hyperactivity disorder (ADHD).Methods: In a 5-week forced-dose titration phase, subjects were randomized to either oral double-blind AMPH ER TAB 5-mg starting dose or matching placebo, once daily in the morning. Safety and efficacy assessments were completed weekly. After visit 3, subjects received 20 mg for 14 ± 3 days before visit 5. At visit 5, efficacy assessments included the administration of serial Permanent Product Measure of Performance (PERMP) tests predose and at 0.5, 1, 2, 4, 8, 10, 12, 13, and 14 hours postdose. The primary efficacy endpoint was the mean PERMP Total score (PERMP-T) across postdose time points during the visit 5 serial PERMPs. Safety was monitored by adverse events (AEs) assessed at each visit, Columbia Suicide Severity Rating Scale (C-SSRS), vital signs, weight, physical examination, and assessment of sleep, appetite, mood, and psychotic AEs. The study was conducted from February 2019 to October 2019.Results: Of 130 randomized subjects, 127 were in the intent-to-treat (ITT) population and 91 completed the study. The mean PERMP-T across all postdose time points at visit 5 was statistically significantly higher in the AMPH ER TAB group than in the placebo group (302.8 vs 279.6; P = .0043). Numerical differences favoring AMPH ER TAB were seen at all time points, with statistically significant improvements in the AMPH ER TAB group at 30 minutes and 1, 2, 4, 8, and 13 hours postdose, although the 10-, 12-, and 14-hour time points were not significant. Common AEs included decreased appetite, insomnia, and dry mouth. The majority of treatment-emergent AEs were mild to moderate in severity, and no serious AEs, as defined by the US Food and Drug Administration, were reported.Conclusions: AMPH ER TAB demonstrated efficacy in treatment of symptoms of ADHD in adults, with an anticipated safety profile.Trial Registration: ClinicalTrials.gov identifier: NCT03834766.

Finding the "Sweet Spot": Sharing the decision-making in ADHD treatment selection.

BACKGROUND: Stimulants are often prescribed as first-line therapy for attention-deficit/hyperactivity disorder. Currently, there are many therapeutic options available for clinicians and families to consider when making the decision to use a medication. In practice, selection of a stimulant medication for ADHD is highly personalized and can be narrowed down to two major factors: finding the optimal duration of the medication effect, and then estimating a starting dose and subsequently "fine-tuning" the medication to the optimal dosage of the medication. With the possibility of titrating to an optimal stimulant dosage within one prescription of a liquid stimulant, prescribers can recruit the parent/caregiver to actively participate in managing the transition to medication, allowing for greater ownership and a sense of shared control over the process. CASE PRESENTATION: The short case series offers a communication method by which clinicians can apply the principles of shared decision-making in helping the parent or caregiver of a newly diagnosed patient with ADHD make informed decisions about medication selection, and to obtain a greater sense of comfort with the new medication regimen. CONCLUSIONS: Much has been published on the importance of clinicians and their patients fostering an environment of clear and unrestricted information-sharing. This short case series illustrates the effectiveness of this approach. Once parents are comfortable with the decision to start drug treatment for ADHD, it is incumbent upon the healthcare provider to ensure that an open channel of communication is maintained, and that parent/caregivers are encouraged to raise concerns as soon as possible.

A single-dose, comparative bioavailability study comparing amphetamine extended-release oral suspension with extended-release mixed amphetamine salts capsules.

BACKGROUND: To evaluate the relative bioavailability of a single dose of amphetamine extended-release oral suspension (AMPH EROS) compared with a single dose of extended-release mixed amphetamine salts (ER MAS) in healthy, fasted adult subjects. METHODS: The study population consisted of healthy adult volunteers. The study drug used in this study was 7.5 mL of 2.5 mg/mL AMPH EROS equivalent to 18.8 mg of amphetamine base administered after an overnight fast of at least 10 hours. AMPH EROS comprises a 3.2:1 enantiomeric ratio of d-amphetamine to l-amphetamine. The reference product was one 30 mg ER MAS capsule (equivalent to 18.8 mg of amphetamine base). Relative bioavailability between the products was determined by a statistical comparison of the area under the curve and maximum concentration (Cmax) for d-amphetamine and l-amphetamine. PK (PK) blood samples were collected prior to dosing (0-hour) and at 1, 2, 3, 3.5, 4, 4.5, 5, 6, 7, 8, 9, 10, 12, 14, 16, 24, 36, 48, and 60 hours after drug administration, totaling 20 samples in each period. RESULTS: The mean subject age was 35.0 (standard deviation ±8) years, and the overall study population comprised 19 (63.3%) males and 11 (36.7%) females. The contrasts for geometric mean ratios for all assessed PK parameters (for both l- and d-amphetamine) between the test article AMPH EROS and reference product ER MAS fell within the prescribed 80% to 125% limits. CONCLUSIONS: The overall PK profile of single-dose AMPH EROS 7.5 mL was found to be comparable with a single dose of oral ER MAS 30 mg.

Assessing Palatability of a New Amphetamine Extended-Release Tablet Formulation for the Treatment of ADHD.

INTRODUCTION/OBJECTIVE: ADHD is, for many people, a lifelong disease that requires chronic medication use. Stimulant therapy is often recommended as first-line treatment for ADHD. Adherence to stimulant treatment among patients diagnosed with ADHD is poor. Major regulatory agencies have recommended measurement of palatability for new tablet formulations. A new amphetamine extended-release tablet (AMPH ER TAB) for the treatment of attention-deficit/hyperactivity disorder (ADHD) was developed. The AMPH ER TAB has a bubblegum flavor and can be chewed or swallowed whole. In 2016, the FDA developed a draft guidance document on the topic of chewable drug tablet formulation palatability. METHODS: A palatability study of the AMPH ER TAB using the 2016 FDA guidance was conducted. Subjects were asked to assess the taste, aftertaste, and mouthfeel of the tablet formulation using a short questionnaire. Scores from the questionnaire were rated and presented. RESULTS: The substudy assessed 35 subjects with a mean age of 38 (±11) years. Subjects were predominantly male, non-Hispanic, and White. Most subjects rated the oral sensation/mouth feel and taste of the tablet as positive (pleasant to very pleasant) (70.1% and 83.6%, respectively). Additionally, 86.6% of the subjects rated the strength of the taste as neutral (moderate taste) or positive (mild to no taste). Finally, 82.1% of all subjects rated the aftertaste as positive (pleasant to very pleasant) and 92.5% of subjects rated the strength of the aftertaste as neutral or positive (mild to no taste). The trends in evaluation scores for each question were similar regardless of whether the ER chewable tablet was administered under fasted or fed conditions. CONCLUSION: The positive palatability data presented here will be useful for future "real-world" assessments of adherence to treatment with the AMPH ER TAB. Enhanced adherence may bolster the argument that taste, mouthfeel, and aftertaste are critical determinants of treatment adherence.

Single-Dose Pharmacokinetics of Amphetamine Extended-Release Oral Suspension in Healthy Adults.

Purpose: This single-dose pivotal study evaluated the pharmacokinetics of amphetamine extended-release oral suspension (AMPH EROS) under fasted and fed conditions and the relative bioavailability of AMPH EROS and immediate-release mixed amphetamine salts (IR MAS) in adults. Methods: This open-label, randomized, three-period, three-treatment, six-sequence crossover study enrolled 30 healthy adult participants who were randomly assigned to receive either 1 dose of AMPH EROS 18.8 mg under fed or fasted conditions or 30 mg of IR MAS under fasted conditions. Participants crossed over with a 7-day washout period between each of the three periods. Plasma samples were measured for Cmax, AUC0-t, AUC0-5, AUC5-t, and AUC0-∞ for comparative bioavailability. Results: The geometric mean ratios for Cmax, AUC0-t, and AUC0-∞ were within the 90% confidence limits [80.0%, 125.0%] for comparable bioavailability. There was no food effect for AMPH EROS. Both the AMPH EROS and IR MAS formulations were generally well tolerated with no serious adverse events reported. Conclusions: The bioavailability of a single dose of AMPH EROS was comparable to two 15 mg doses of IR MAS, given 4 hr apart, with no food effect or safety concerns observed.

Single-dose pharmacokinetics of amphetamine extended-release tablets compared with amphetamine extended-release oral suspension.

OBJECTIVE: Evaluate the relative bioavailability of single-dose amphetamine extended-release tablet (AMPH ER TAB) 20 mg, swallowed whole or chewed, and amphetamine extended-release oral suspension (AMPH EROS) 2.5 mg/mL; evaluate food effect on AMPH ER TAB. METHODS: Healthy volunteers (18-55 years) were randomized to 1 dose of AMPH ER TAB 20 mg swallowed (fasted), chewed (fed/fasted), or 20 mg AMPH EROS (fasted). A crossover study design was used. Plasma samples were collected each period predose and at time points to 60 hours postdose. d- and l-amphetamine were measured and pharmacokinetic (PK) was calculated (90% confidence intervals of the ratios of the plasma levels) for AUC0-t, AUC0-∞, and Cmax. Comparative relative bioavailability between formulations was determined when ratios were within 80% and 125%. Safety was also assessed. RESULTS: Thirty-two subjects completed the study. AMPH ER TAB swallowed versus AMPH EROS (fasted): for d- and l-amphetamine, the total and peak exposure was similar: d: AUC0-t: 100.68% to 108.08%, AUC0-∞: 101.47% to 109.52%, Cmax: 98.10% to 103.17%; l: AUC0-t: 100.31% to 108.57%, AUC0-∞: 101.27% to 111.09%, Cmax: 98.2% to 103.37%. For d- and l-amphetamine when the tablet is swallowed whole, Tmax was 5.00 hours (with a range of 2.00-9.00 hours). AMPH ER TAB chewed versus AMPH EROS (fasted): for d- and l-amphetamine, the total and peak exposure was similar: d: AUC0-t: 99.23% to 106.62%, AUC0-∞: 99.58% to 107.59%, Cmax: 99.91% to 105.14%; l: AUC0-t: 98.16% to 106.35%, AUC0-∞: 98.44% to 108.11%, Cmax: 99.53% to 104.75%. For d- and l-amphetamine when the tablet has been chewed, Tmax was 5.00 hours (with a range of 3.00-7.00 hours). PK results were similar for patients in the fasted and fed groups, indicative of no presence of food effect. No serious adverse events (AEs) were reported, overall AE profiles between the tablet and oral suspension were comparable without any unanticipated safety concerns. CONCLUSIONS: Single doses of AMPH ER TAB for both d- and l-amphetamine demonstrated comparable bioavailability to a 20 mg dose of AMPH EROS, 2.5 mg/mL under fasted conditions when chewed and swallowed whole, and demonstrated equivalent peak and overall exposure without apparent food effect. AMPH ER TAB was well-tolerated and consistent with adverse events noted in other amphetamine formulations.

The mouse curly whiskers (cw) mutations are recessive alleles of hephaestin-like 1 (Hephl1).

The spontaneous, curly whiskers mutation (abbreviated cw) generates kinky, brittle vibrissae in homozygous mice. Although cw has been mapped to the centromeric end of mouse Chromosome 9, no particular gene has been causally implicated, and this lack of genetic assignment has stymied cw's complete molecular and functional analysis. As a foundation for its positional cloning, we have fine-mapped cw to a small, 0.57 Mb interval that contains only three skin-expressed genes, including hephaestin-like 1 (Hephl1), which encodes a membrane-bound, multi-copper ferroxidase. Sequence analysis of all Hephl1 coding regions in cw/cw mutants revealed a single-base-pair substitution that alters Hephl1 mRNA splicing, and is specific to the cw allele, only. Sequence analysis of a second, independent, re-mutation to curly whiskers (that we verified by complementation testing with cw and have designated cw 2J ) revealed a distinct defect in Hephl1 (a frame-shifting, single-base-pair insertion) that is specific to cw 2J . The results presented strongly suggest that defects in the Hephl1 gene are the molecular basis of the classical, curly-whiskers mutant phenotypes.

Early-Onset Efficacy and Safety Pilot Study of Amphetamine Extended-Release Oral Suspension in the Treatment of Children with Attention-Deficit/Hyperactivity Disorder.

OBJECTIVE: To determine whether amphetamine extended-release oral suspension (AMPH EROS) has an onset of effect at 30 minutes postdose in children with attention-deficit/hyperactivity disorder (ADHD). METHODS: This randomized, double-blind, two-treatment, two-sequence, placebo-controlled crossover pilot study enrolled subjects aged 6-12 years with ADHD and ADHD-Rating Scale-5 scores of ≥90th percentile for sex and age. An optimized dose of 5-20 mg/day of AMPH EROS was determined during a 1-week open-label dose optimization phase based on medication history, symptom control, and tolerability. Subjects completed a practice laboratory classroom then received 1 day of double-blind active drug or placebo each in random sequence during two double-blind laboratory classroom days. Subjects completed the first double-blind laboratory classroom, returned to open-label drug for 5 days, and then crossed over on day 6 during a second double-blind laboratory classroom. Double-blind dose was fixed at AMPH EROS 15, 17.5, or 20 mg. The primary end point was change from predose in the Swanson, Kotkin, Agler, M-Flynn, Pelham-Combined (SKAMP-C) Rating Scale score at 30 minutes postdose on two double-blind days. The key secondary end points were change from predose in the SKAMP-C score at 3 hours postdose for AMPH EROS compared with placebo and change from baseline Permanent Product Measure of Performance (PERMP) scores at 30 minutes and 3 hours postdose compared with placebo. Safety assessments included vital signs and adverse events (AEs). RESULTS: Eighteen subjects were enrolled in the study (14 males and 4 females) with a mean age of 9 years. At both 30 minutes and 3 hours postdose, changes from baseline in SKAMP-C for AMPH EROS versus placebo were statistically significant (p < 0.01 and p = 0.0002, respectively). PERMP scores were not statistically significantly improved at 30 minutes postdose for AMPH EROS relative to the placebo group. PERMP scores were statistically significantly improved at 3 hours postdose for AMPH EROS relative to the placebo group (PERMP problems attempted treatment difference least-squares [LS] mean [SE] = 60.3 [12.93], p = 0.0003; PERMP problems correct treatment difference LS mean [SE] = 61.6 [13.16], p = 0.0003). AEs (>10%) during the open-label phase included upper respiratory tract infection, fatigue, upper abdominal pain, headache, decreased appetite, and affect lability. CONCLUSIONS: AMPH EROS was effective in reducing ADHD symptoms at 30 minutes postdose as indicated by SKAMP-C score improvement, although improvements in PERMP scores at 30 minutes were not statistically significant. AEs were mild or moderate and consistent with those of other extended-release amphetamines.

Emergency use of uridine triacetate for the prevention and treatment of life-threatening 5-fluorouracil and capecitabine toxicity.

BACKGROUND: Increased susceptibility to 5-fluorouracil (5-FU)/capecitabine can lead to rapidly occurring toxicity caused by impaired clearance, dihydropyrimidine dehydrogenase deficiency, and other genetic variations in the enzymes that metabolize 5-FU. Life-threatening 5-FU overdoses occur because of infusion pump errors, dosage miscalculations, and accidental or suicidal ingestion of capecitabine. Uridine triacetate (Vistogard) was approved in 2015 for adult and pediatric patients who exhibit early-onset severe or life-threatening 5-FU/capecitabine toxicities or present with an overdose. Uridine triacetate delivers high concentrations of uridine, which competes with toxic 5-FU metabolites. METHODS: In 2 open-label clinical studies, patients who presented with a 5-FU/capecitabine overdose or an early onset of severe toxicities were treated. Patients received uridine triacetate as soon as possible (most within the first 96 hours after 5-FU/capecitabine). Outcomes included survival, resumption of chemotherapy, and safety. Their survival was compared with the survival of a historical cohort of overdose patients who received only supportive care. RESULTS: A total of 137 of 142 overdose patients (96%) treated with uridine triacetate survived and had a rapid reversal of severe acute cardiotoxicity and neurotoxicity; in addition, mucositis and leukopenia were prevented, or the patients recovered from them. In the historical cohort, 21 of 25 patients (84%) died. Among the 141 uridine triacetate-treated overdose patients with a diagnosis of cancer (the noncancer patients included 6 intentional or accidental pediatric overdoses), 53 resumed chemotherapy in < 30 days (median time after 5-FU, 19.6 days), and this indicated a rapid recovery from toxicity. Adverse reactions in patients receiving uridine triacetate included vomiting (8.1%), nausea (4.6%), and diarrhea (3.5%). CONCLUSIONS: In these studies, uridine triacetate was a safe and effective lifesaving antidote for capecitabine and 5-FU overexposure, and it facilitated the rapid resumption of chemotherapy. Cancer 2017;123:345-356. © 2016 American Cancer Society.

Auxotrophy-Based Detection of Hyperornithinemia in Mouse Blood and Urine

Abstract Gyrate atrophy of the choroid and retina (GACR) is a hereditary form of progressive blindness caused by homozygosity for loss-of-function mutations in the ornithine aminotransferase gene (Oat). The high levels of circulating ornithine that lead to ophthalmic symptoms in young adults are also displayed by 2 ornithine aminotransferase (OAT)-deficient mouse models of GACR. Here, we have developed an inexpensive and quantitative bacteria-based test for detecting hyperornithinemia in blood or urine samples from these mutant mice, a test that we suggest could be used to facilitate the identification and treatment of OAT-deficient humans before the onset of visual impairment.

The mouse wellhaarig (we) mutations result from defects in epidermal-type transglutaminase 3 (Tgm3).

The recessive wellhaarig (we) mutations, named for the wavy coat and curly whiskers they generate in homozygotes, have previously been mapped on mouse Chromosome 2. To further limit the possible location of the we locus, we crossed hybrid (C57BL/6×AKR)F1, we(4J)/+ females with AKR, we(4J)/we(4J) mutant males to create a large backcross family that was typed for various microsatellite markers and single-nucleotide polymorphisms (SNPs) that distinguish strains AKR and B6. This analysis restricted the location of we(4J) between sites that flank only one gene known to be expressed in skin: epidermal-type transglutaminase 3 (Tgm3). To test Tgm3 as a candidate for the basis of the wellhaarig phenotype we took two approaches. First, we sequenced all Tgm3 coding regions in mice homozygous for four independent, naturally-occurring wellhaarig alleles (we, we(Bkr), we(3J) and we(4J)) and found distinct defects in three of these mutants. Second, we crossed mice homozygous for an induced mutant allele of Tgm3 (Tgm3(Btlr)) with mice heterozygous for one of the wellhaarig alleles we possess (we(4J) or we(Bkr)) to test for complementation. Because the progeny inheriting both a recessive we allele and a recessive Tgm3(Btlr) allele displayed wavy hair, we conclude that the classic wellhaarig mutations result from defects in Tgm3.

The retarded hair growth (rhg) mutation in mice is an allele of ornithine aminotransferase (Oat).

Because of the similar phenotypes they generate and their proximate reported locations on Chromosome 7, we tested the recessive retarded hair growth (rhg) and frizzy (fr) mouse mutations for allelism, but found instead that these defects complement. To discover the molecular basis of rhg, we analyzed a large intraspecific backcross panel that segregated for rhg and restricted this locus to a 0.9 Mb region that includes fewer than ten genes, only five of which have been reported to be expressed in skin. Complementation testing between rhg and a recessive null allele of fibroblast growth factor receptor 2 eliminated Fgfr2 as the possible basis of the retarded hair growth phenotype, but DNA sequencing of another of these candidates, ornithine aminotransferase (Oat), revealed a G to C transversion specifically associated with the rhg allele that would result in a glycine to alanine substitution at residue 353 of the gene product. To test whether this missense mutation might cause the mutant phenotype, we crossed rhg/rhg mice with mice that carried a recessive, perinatal-lethal, null mutation in Oat (designated OatΔ herein). Hybrid offspring that inherited both rhg and OatΔ displayed markedly delayed postnatal growth and hair development, indicating that these two mutations are allelic, and suggesting strongly that the G to C mutation in Oat is responsible for the retarded hair growth phenotype. Comparisons among +/+, rhg/+, rhg/rhg and rhg/OatΔ mice showed plasma ornithine levels and ornithine aminotransferase activities (in liver lysates) consistent with this assignment. Because histology of 7- and 12-month-old rhg/rhg and rhg/OatΔ retinas revealed chorioretinal degeneration similar to that described previously for OatΔ/OatΔ mice, we suggest that the rhg mutant may offer an ideal model for gyrate atrophy of the choroid and retina (GACR) in humans, which is also caused by the substitution of glycine 353 in some families.

Efficacy of glucarpidase (carboxypeptidase g2) in patients with acute kidney injury after high-dose methotrexate therapy.

STUDY OBJECTIVE: Because the incidence rate of renal impairment is 2-10% for patients treated with high-dose methotrexate and renal impairment develops in 0-12.4% of patients treated for osteosarcoma, we sought to evaluate the efficacy of glucarpidase, a recently approved drug that rapidly hydrolyzes methotrexate to inactive metabolites, which allows for nonrenal clearance in patients with delayed renal methotrexate elimination. DESIGN: Pooled analysis of efficacy data from four multicenter single-arm compassionate-use clinical trials using protocols from 1993 to 2007. PATIENTS: Of 476 patients with renal toxicity and delayed methotrexate elimination who were treated with intravenous glucarpidase for rescue after high-dose methotrexate, 169 patients had at least one preglucarpidase (baseline) plasma methotrexate concentration greater than 1 µmol/L and one postglucarpidase methotrexate concentration measurement by high-performance liquid chromatography and were included in the efficacy analysis; renal recovery was assessed in 436 patients who had at least one recorded preglucarpidase and postglucarpidase serum creatinine concentration measurement. MEASUREMENTS AND MAIN RESULTS: Efficacy was defined as rapid and sustained clinically important reduction (RSCIR) in plasma methotrexate concentration, with a concentration of 1 µmol/L or lower at all postglucarpidase determinations. Median age of efficacy-evaluable patients was 20 years (range 5 weeks-84 years). Osteosarcoma (36%), non-Hodgkin lymphoma (27%), and acute lymphoblastic leukemia (20%) were the most frequent underlying diagnoses. Median preglucarpidase serum methotrexate was 11.7 µmol/L. At the first (median 15 minutes) through the last (median 40 hours) postglucarpidase measurement, plasma methotrexate concentrations demonstrated consistent 99% median reduction. RSCIR was achieved by 83 (59%) of 140 patients. A total of 64% of patients with renal impairment greater than or equal to Common Terminology Criteria for Adverse Events grade 2 recovered to grade 0 or 1 at a median of 12.5 days after glucarpidase administration. CONCLUSION: Glucarpidase caused a clinically important 99% or greater sustained reduction of serum methotrexate levels and provided noninvasive rescue from methotrexate toxicity in renally impaired patients.

The wooly mutation (wly) on mouse chromosome 11 is associated with a genetic defect in Fam83g.

BACKGROUND: Mice homozygous for the spontaneous wooly mutation (abbreviated wly) are recognized as early as 3-4 weeks of age by the rough or matted appearance of their coats. Previous genetic analysis has placed wly in a 5.9 Mb interval on Chromosome 11 that contains over 200 known genes. Assignment of wly to one of these genes is needed in order to provide probes that would ultimately facilitate a complete molecular analysis of that gene's role in the normal and disrupted development of the mammalian integument. RESULTS: Here, a large intraspecific backcross family was used to genetically map wly to a smaller (0.8 Mb) span on mouse Chromosome 11 that includes fewer than 20 genes. DNA sequencing of the coding regions in two of these candidates known to be expressed in skin has revealed a 955 bp, wly-specific deletion. This deletion, which lies within the coordinates of both Slc5a10 [for solute carrier family 5 (sodium/glucose cotransporter), member 10] and Fam83g (for family with sequence similarity 83, member G), alters the splicing of mutant Fam83g transcripts only, and is predicted to result in a severely truncated (probably non-functional) protein product. CONCLUSION: We suggest that this mutation in Fam83g is the likely basis of the mouse wooly phenotype.

The juvenile alopecia mutation (jal) maps to mouse Chromosome 2, and is an allele of GATA binding protein 3 (Gata3).

BACKGROUND: Mice homozygous for the juvenile alopecia mutation (jal) display patches of hair loss that appear as soon as hair develops in the neonatal period and persist throughout life. Although a report initially describing this mouse variant suggested that jal maps to mouse Chromosome 13, our preliminary mapping analysis did not support that claim. RESULTS: To map jal to a particular mouse chromosome, we produced a 103-member intraspecific backcross panel that segregated for jal, and typed it for 93 PCR-scorable, microsatellite markers that are located throughout the mouse genome. Only markers from the centromeric tip of Chromosome 2 failed to segregate independently from jal, suggesting that jal resides in that region. To more precisely define jal's location, we characterized a second, 374-member backcross panel for the inheritance of five microsatellite markers from proximal Chromosome 2. This analysis restricted jal's position between D2Mit359 and D2Mit80, an interval that includes Il2ra (for interleukin 2 receptor, alpha chain), a gene that is known to be associated with alopecia areata in humans. Complementation testing with an engineered null allele of Il2ra, however, showed that jal is a mutation in a distinct gene. To further refine the location of jal, the 374-member panel was typed for a set of four single-nucleotide markers located between D2Mit359 and D2Mit80, identifying a 0.55 Mb interval where jal must lie. This span includes ten genes-only one of which, Gata3 (for GATA binding protein 3)-is known to be expressed in skin. Complementation testing between jal and a Gata3 null allele produced doubly heterozygous, phenotypically mutant offspring. CONCLUSIONS: The results presented indicate that the jal mutation is a mutant allele of the Gata3 gene on mouse Chromosome 2. We therefore recommend that the jal designation be changed to Gata3jal, and suggest that this mouse variant may provide an animal model for at least some forms of focal alopecia that have their primary defect in the hair follicle and lack an inflammatory component.

Validating a faster method for reconstitution of Crotalidae Polyvalent Immune Fab (ovine).

BACKGROUND: Reconstitution of CroFab(®) (Crotalidae Polyvalent Immune Fab [ovine]) lyophilized drug product was previously performed using 10 mL sterile water for injection followed by up to 36 min of gentle swirling of the vial. CroFab has been clinically demonstrated to be most effective when administered within 6 h of snake envenomation, and improved clinical outcomes are correlated with quicker timing of administration. An alternate reconstitution method was devised, using 18 mL 0.9% saline with manual inversion, with the goal of shortening reconstitution time while maintaining a high quality, efficacious product. METHODS: An analytical study was designed to compare the physicochemical properties of 3 separate batches of CroFab when reconstituted using the standard procedure (10 mL WFI with gentle swirling) and a modified rapid procedure using 18 mL 0.9% saline and manual inversion. The physical and chemical characteristics of the same 3 batches were assessed using various analytic methodologies associated with routine quality control release testing. In addition further analytical methodologies were applied in order to elucidate possible structural changes that may be induced by the changed reconstitution procedure. RESULTS: Batches A, B, and C required mean reconstitution times of 25 min 51 s using the label method and 3 min 07 s (a 88.0% mean decrease) using the modified method. Physicochemical characteristics (color and clarity, pH, purity, protein content, potency) were found to be highly comparable. Characterization assays (dynamic light scattering, analytical ultracentrifugation, LC-MS, SDS-PAGE and circular dichroism spectroscopy were also all found to be comparable between methods. DISCUSSION: When comparing CroFab batches that were reconstituted using the labeled and modified methods, the physicochemical and biological (potency) characteristics of CroFab were not significantly changed when challenged by the various standard analytical methodologies applied in routine quality control analysis. Additionally, no changes in the CroFab molecule regarding degradation, aggregation, purity, structure, or mass were observed. CONCLUSION: The analyses performed validated the use of the more rapid reconstitution method using 18 mL 0.9% saline in order to allow a significantly reduced time to administration of CroFab to patients in need.

The mouse frizzy (fr) and rat 'hairless' (frCR) mutations are natural variants of protease serine S1 family member 8 (Prss8).

Please cite this paper as: The mouse frizzy (fr) and rat 'hairless' (fr(CR)) mutations are natural variants of protease serine S1 family member 8 (Prss8). Experimental Dermatology 2010; 19: 527-532. Abstract: We have previously suggested (based on genetic mapping analysis) that the allelic 'fuzzy' and 'hairless' mutations in the rat are likely orthologues of the mouse frizzy mutation (fr). Here, we analysed three large intraspecific backcross panels that segregated for mouse fr to restrict this locus to a 0.6-Mb region that includes fewer than 30 genes. DNA sequencing of one of these candidates known to be expressed in skin, protease serine S1 family member 8 (Prss8), revealed a T to A transversion associated with the fr allele that would result in a valine to aspartate substitution at residue 170 in the gene product. To test whether this missense mutation might be the molecular basis of this frizzy variant, we crossed fr/fr mice with mice that carried a recessive perinatal lethal mutation in Prss8. Hybrid offspring that inherited both fr and the Prss8 null allele displayed abnormal hair and skin, showing that these two mutations are allelic, and suggesting strongly that the T to A mutation in Prss8 is responsible for the mutant frizzy phenotype. Sequence analysis of all Prss8 coding regions in the 'hairless' rat identified a 12-bp deletion in the third exon, indicating that mouse fr and the rat 'hairless' mutations are indeed orthologues. However, this analysis failed to detect any alterations to Prss8 coding sequences in the allelic 'fuzzy' rat variant.