Development and Validation of a Gamma Globin RT-Ddpcr Exploratory Biomarker for Sickle Cell Phase 1 Clinical Trial Fis 002-2020

FTX-6058, a selective and potent binder of embryonic ectoderm development protein (EED), is being investigated in Sickle Cell Disease (SCD). In-vitro and pre-clinical Townes mouse studies show FTX-6058 upregulates expression of the gamma globulin gene leading to increased levels of fetal hemoglobin (HbF). In human clinical trials, as an early indicator of FTX-6058 induced gamma globulin expression, a reverse transcriptase droplet digital PCR (RT-ddPCR) assay was developed and validated by Precision for Medicine. Versus RT-qPCR, RT-ddPCR gives absolute copy number, does not require a standard curve, and is more precise and reproducible for low expressed targets 1,2. Precision for Medicine developed and validated RT-ddPCR assays for the target globin genes α, β, and γ and for the housekeeping genes TFRC and OAZ1. RNA isolated from 3 healthy and 3 SCD affected individuals was used for development and validation of the assay. The upper and lower limits of quantification were 120,000 and 10.5 copies/20μL reaction, respectively. For samples with >50 copies/20μL reaction, the CV for technical replicates was <20% for all transcripts. Furthermore, Precision for Medicine demonstrated SCD affected individuals express approximately 15-fold more γ globulin versus non affected individuals. Fulcrum utilized the globin RT-ddPCR assay validated by Precision for Medicine in the FTX-6058 phase 1 clinical trial FIS 002-2020. 1 Zhao Y, Xia Q, Yin Y, Wang Z (2016), Comparison of Droplet Digital PCR and Quantitative PCR Assays for Quantitative Detection of Xanthomonas citri Subsp. citri. PLoS ONE 11(7): e0159004. doi:10.1371/journal.pone.0159004 2 Taylor SC, Laperriere G, Germain H (2017), Droplet Digital PCR versus qPCR for gene expression analysis with low abundant targets: from variable nonsense to publication quality data. Scientific Reports 7(2409): DOI:10.1038/s41598-017-02217-x Disclosures Roth: Fulcrum Therapeutics, Inc.: Current Employment, Current equity holder in publicly-traded company. Yang: Fulcrum Therapeutics, Inc.: Consultancy. Tsavachidou: Fulcrum Therapeutics, Inc.: Consultancy. Davis: Fulcrum Therapeutics, Inc.: Consultancy.

Hypogammaglobulinemia and therapeutic use of gamma globulin

In the Soviet Union, gammaglobulin was first obtained in 1946 by Kholchev and Kolesnikova from the blood serum of donors. At first, it was used to prevent measles, and then, as the content of various antibodies in it was studied, it began to be used for poliomyelitis (Leitman, Strakhova, Denisenko, Bogdanov), Botkin's disease (Ananiev, Grachev, Fabrikantov), ​​whooping cough (Khropetskaya), scarlet fever ( Kaushanskaya, Zhagullo, Mauerman). Gammaglobulins were also obtained from the blood serum of animals, which were successfully used for rabies (Selimov, Durasova, Kovalevskaya. Kobrinsky, Chun-syun), plague (Semenova, Ponomareva), smallpox (Mirosennikova). Gammaglobulin in industrial conditions is prepared from the placental serum of healthy women in labor.

Major Complication Following Kawasaki Disease in an Infant—The Development of Apical Infarction and Aneurysm Formation

Considerable advances have occurred in the understanding of Kawasaki disease, with a substantial drop in morbidity and mortality following the infusion of gamma globulin during the acute phase. Nevertheless, major complications may still occur. A 27-year-old male presented as an infant of 11 weeks when he was diagnosed as having Kawasaki disease. He was appropriately treated with aspirin and a gamma globulin infusion following his diagnosis 5 days after the onset of his illness. Despite that, he went on to develop coronary aneurysms. He represented a few weeks later with a history of inconsolable crying associated with pallor, suggestive of ischaemic chest pain. A repeat echocardiogram revealed infarction of the apex of the left ventricle with localised thrombus formation. There were persistent aneurysms within both coronary artery systems. A further infusion of gamma globulin was given. In view of the thrombus formation, he was started on warfarin. The thrombus gradually resolved with the development of a clearly defined left ventricular apical aneurysm. He has remained on warfarin, aiming for an international normalised ratio (INR) level of 2 to 2.5. He developed mild left ventricular dysfunction during late childhood, which improved following the commencement of an angiotensin-converting enzyme (ACE) inhibitor. Despite his ventricular aneurysm, there has been no documented evidence of ventricular tachycardia over the years. Repeated testing initially by nuclear perfusion scans and then by stress echocardiograms failed to show any inducible ischaemia apart from the apical ventricular aneurysm. A recent computed tomography (CT) coronary angiogram revealed an ectatic origin of the left main and the right coronary arteries with mild calcification involving the mid-portion of the latter and slight calcification of the former. His raised cholesterol level has responded well to a statin. Despite the persistence of the ventricular aneurysm, he continues to be managed conservatively, as he has remained well. The question arises as to what the long-term implications are of his left ventricle apical aneurysm. Should it be excised? Is he at risk for ventricular tachycardia and sudden death? In addition, although the coronary aneurysms have resolved, the CT coronary angiogram shows calcium plaques in both coronary arteries at the site of the earlier aneurysms. This finding raises the question as to whether all children who develop coronary artery aneurysms following Kawasaki disease should have a CT coronary angiogram performed in adulthood.

Human immune globulin 10% with recombinant human Hyaluronidase- A Review

Primary immunodeficiency disorder (PID) refers to a heterogeneous cluster of over 350 syndromes that upshot from defects in the immune system development or function. PIDs are broadly classified as disorders of adaptive immunity or innate immunity. The enhanced efficacy of human immune serum globulin 10% with recombinant human Hyaluronidase with comparison to blood vessel human gamma globulin is a very prospective open-label study for PID. Treatment of primary immunological disorder diseases (PIDD) with Subcutaneous(SC) infusions of immune gamma globulin headed by an injection of hyazyme to extend SC tissue porousness was evaluated in two consecutive, prospective, non-controlled, multi-center studies. HYQVIA could be a subcutaneously mediated medication to treat the primary immunological disorder in adults. ENHANZE® drug delivery technology relies on the proprietary rHuPH20 macromolecule that facilitates the SC delivery of co administered medical specialty. Recombinant Human Hyaluronidase works by degrading the glycosaminoglycan hyaluronan, which plays a role in resistance to excessive flow of fluid within the Subcutaneous matrix, limiting massive volume SC drug delivery, dispersion, and absorption. Co-administration of recombinant Hyazyme with partner therapies can overcome administration time and volume barriers associated with existing SC therapeutic formulations.

Novel phenotypes of coronavirus disease: a temperature-based trajectory model

Background Coronavirus disease has heterogeneous clinical features; however, the reasons for the heterogeneity are poorly understood. This study aimed to identify clinical phenotypes according to patients’ temperature trajectory. Method A retrospective review was conducted in five tertiary hospitals in Hubei Province from November 2019 to March 2020. We explored potential temperature-based trajectory phenotypes and assessed patients’ clinical outcomes, inflammatory response, and response to immunotherapy according to phenotypes. Results A total of 1580 patients were included. Four temperature-based trajectory phenotypes were identified: normothermic (Phenotype 1); fever, rapid defervescence (Phenotype 2); gradual fever onset (Phenotype 3); and fever, slow defervescence (Phenotype 4). Compared with Phenotypes 1 and 2, Phenotypes 3 and 4 had a significantly higher C-reactive protein level and neutrophil count and a significantly lower lymphocyte count. After adjusting for confounders, Phenotypes 3 and 4 had higher in-hospital mortality (adjusted odds ratio and 95% confidence interval 2.1, 1.1–4.0; and 3.3, 1.4–8.2, respectively), while Phenotype 2 had similar mortality, compared with Phenotype 1. Corticosteroid use was associated with significantly higher in-hospital mortality in Phenotypes 1 and 2, but not in Phenotypes 3 or 4 (p for interaction < 0.01). A similar trend was observed for gamma-globulin. Conclusions Patients with different temperature-trajectory phenotypes had different inflammatory responses, clinical outcomes, and responses to corticosteroid therapy.

Case Report: Hypothyroidism Misdiagnosed as Fulminant Myocarditis in a Child

Background: Hypothyroidism can lead to bradycardia, reduced cardiac output, cardiac enlargement, and abnormal electrocardiogram. However, hemodynamic instability and malignant arrhythmias due to hypothyroidism is rarely reported in children.Patient Findings: We report the case of a child with third-degree atrioventricular block, cardiogenic shock, and Adams Stokes Syndrome, who was initially misdiagnosed with fulminant myocarditis and was later found to have hypothyroidism during treatment.Summary: The child's condition did not improve after the administration of gamma globulin, methylprednisolone, and isoproterenol. Even after the placement of temporary pacemakers, the therapeutic effect was still not ideal. Upon reviewing the medical history, the child's condition improved rapidly after levothyroxine supplementation.Conclusions: Hypothyroidism is a common disease, but secondary severe cardiovascular lesions are particularly rare in children. Therefore, the delay in diagnosis can lead to serious cardiovascular manifestations. When pediatric patients develop severe AVB and bradycardia, hypothyroidism should be considered as a possible cause.

Factitious Total Triiodothyronine(T3) Elevation in a Euthyroid Patient With Paraproteinemia

Background: We report a rare case of a patient treated with levothyroxine for hypothyroidism who also had paraproteinemia and was found to have a clinically inconsistent elevation of T3 by RIA. Clinical Case: A 72 Year old African American female with a history of hypothyroidism and IgG kappa Multiple Myeloma (MM) was admitted to the hospital for altered mental status. Her hypothyroidism had been well controlled for years on a stable dose of levothyroxine 0.075mg daily. Review of systems were negative pertinent to thyroid dysfunction. Family history: negative for thyroid disease. On physical exam, an elderly female clinically euthyroid without palpable thyromegaly but was confused and disoriented. Initial Vital signs: BP 117/67, HR 62, RR 14, T 98, SpO2 99% on room air. BMI 19. EKG: normal sinus rhythm, CXR: normal, TSH: 6.27 (0.55-4.78 uIU/mL), total T3: &gt;600 (60-181ng/dL), total T4: 4.5 (3.2-12.6 ug/dL), FT4: 1.22 (0.89-1.76 ng/dL), hemoglobin: 6.6 (12-16 g/dL), hematocrit: 20.9 (38-47 %), Na: 132 (136-145 mmol/L), K: 4.0 (3.5-5.1 mmol/L), Cl: 104 (98-10/ mmol/L), BUN: 45 (20-31 mmol/L), creatinine: 2.8 (0.6-1.0 mg/dL), total protein: 10.1 (5.7-8.2 g/dL), albumin: 1.8 (3.4- 5.0 g/dL), A:G ratio: 0.22 (0.60-1.50 mmol/L). Serum protein electrophoresis revealed Gamma Globulin 5.8 (0.8-1.7 g/dL), Kappa 9270 mg/L (3.3 -19.4 mg/L) Lambda 9.3 (5.7-26.3mg/L), K/L 996.7 (0.26 -1.65), B2 - macroglobulin: 17.9 (ref: &lt;or= 2.51mg/L) which is consistent with an M- spike migrating in the gamma globulin region. Serum TPO, TG, TSI antibodies were negative. Further testing again reported Total T3 &gt;600 with normal reverse T3 21(8-25 ng/dL). Conclusion: Rare cases of factitious elevations of thyroid hormone have been reported in patients with elevated abnormal IgG or IgA proteins having high binding affinity for thyroid hormone.[1] This hypothyroid patient was clinically and biochemically euthyroid except for a dramatic but clinically inconsistent elevated total T3. She also had multiple myeloma with paraproteinemia (IgG Kappa M spike). The few cases reported to date have shown factitious elevation of either or both total T4 and total T3. In our case the factitious elevation was limited to total T3. We alert clinicians to be aware of factitious elevation of thyroid hormones due to high affinity binding to immunoglobulins. In our case this caused spurious elevation of total T3, but not total T4, in a patient with multiple myeloma and an IgG kappa M spike paraprotein. Reference: 1: Marianna Antonopoulou, Arnold Silverberg, “Spurious T3 Thyrotoxicosis Unmasking Multiple Myeloma”, Case Reports in Endocrinology, vol. 2013, Article ID 739302, 3 pages, 2013. https://doi.org/10.1155/2013/739302

Low total gamma globulin level discovery at diffuse large B cell lymphoma diagnosis predicts high risk of infection-related death: data from a monocentric retrospective study

Objective: Diffuse-large-B-cell-lymphoma (DLBCL) can complicate B-cell-primary-immunodeficiencies (PIDs) course or induce total gamma-globulin level (TGL) lowering, whose clinical status as an effective secondary immunodeficiency (SID) remains unspecified. This study aims to assess the frequency, clinical and prognostic relevance of the lowest TGLs discovered at DLBCL diagnosis. Results: In a two year monocentric retrospective cohort, 96 patients diagnosed with DLBCL who had a serum electrophoresis (SEP) were included. Patients were divided into the lowest (L)- and the highest (H)-TGLs (TGL ≤5.5 g/L and TGL >5.5 g/L) subgroups and compared for outcomes, including fatal infectious events. In our cohort, 12 (12.5%; 8 males; median age: 68 [55—82] years) exhibited L-TGL. There was no differences regarding demographics, Ann-Arbor-lymphoma-stages, inflammatory parameters or chemotherapy regimen between both groups. However, overall (10/12, 83.3% versus 22/96, 26.2%; p=0.03) and infection-related death rates (10/12, 83% versus 6/96, 6.2%; p<0.001) were significantly higher in the L-TGL group. Conclusion: We demonstrate for the first time the strong negative impact of L-TGL on overall and infection-related mortality in DLBCL. Prospective studies should distinguish DLBCL-related SIDs from preexisting humoral PIDs, using biomolecular testing and post-treatment TGLs monitoring to determine the best management strategy for infectious risk during DLBCL treatment in L-TGL context.