Subcutaneous Injection Site Research Articles

Abstract 5060: Discrepancy between MMP-9 and its fibronectin-like domain in tumor growth and invasion.

Abstract Tumors are often compared to wounds that do not heal, where the crosstalk between tumor cells and their surrounding stroma is crucial at all stages of development from the initial primary growth to metastasis. Similar to wound healing, fibroblasts in the tumor stroma differentiate into myofibroblasts, also referred to as “cancer-associated fibroblasts” (CAFs), primarily, but not exclusively, in response to transforming growth factor-β (TGF-β). Myofibroblasts in turn enhance tumor progression by remodeling the stroma. Among molecules implicated in stromal remodeling, matrix metalloproteinases (MMPs), and MMP-9 in particular, play a prominent role. However, the mechanisms that regulate MMP-9 activation and function remain poorly understood. Recent evidence indicates that tumor cell surface association of MMP-9 is an important event in its activation, and more generally in tumor growth and invasion. Based on these observations, we addressed the potential association of MMP-9 activity with cell-surface recruitment on human fibroblasts. We show for the first time that recruitment of MMP-9 to the MRC5 fibroblast cell surface occurs through the fibronectin-like (FN) domain, found only in MMP-9 and MMP-2. Functional assays suggest that the active form of MMP-9 triggers α-smooth muscle actin (αSMA) expression in resting fibroblasts that reflects myofibroblast differentiation, possibly through TGF-β activation. Xenograft experiments using HT1080 fibrosarcoma or MDA-MD231 breast adenocarcinoma cells stably expressing the FN domain of MMP-9 in NOD/SCID mice revealed no changes in primary tumor growth. However, in the context of metastasis, expression of the FN domain by these same tumor cells dramatically increases their metastatic proclivity whereas expression of wt MMP-9 either promotes no change or actually reduces the number of metastases. Curiously, xenografts of SW480 colorectal adenocarcinoma cells stably expressing the FN domain of MMP-9 display reduced growth at both the primary (subcutaneous) injection site and the lungs, in experimental metastasis assays, of NOD/SCID mice. This discrepancy is believed to be due to the FN domain that may modulate MMP-9 activity and TGF-β activation in different ways, depending on the tumor cell type. These observations suggest a dual role of MMP-9 and its FN domain in primary tumor growth and metastasis, underscoring the notion that the effect of MMP-9 on tumor cells may depend on their response to TGF-β activation and highlighting possible protective effects of MMPs in tumor progression and invasion. Citation Format: Cynthia Dayer. Discrepancy between MMP-9 and its fibronectin-like domain in tumor growth and invasion. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5060. doi:10.1158/1538-7445.AM2013-5060

Type 1 Ig-E mediated allergy to human insulin, insulin analogues and beta-lactam antibiotics

Insulin, a crucial therapeutic agent for diabetes mellitus, has been rarely associated with hypersensitivity events. We present a 69-year-old type-2 diabetic patient with urticariform lesions on the sites of subcutaneous injection of insulin. The patient denied any known allergies, except for an unspecific cutaneous reaction after intramuscular penicillin administration in childhood. Prick tests revealed positive reactions to all tested human insulins and insulin analogues. Serum IgE levels were above normal range and RAST tests were positive for human, bovine and porcine insulins, as well as beta-lactams. Type 1 IgE-mediated allergy to insulin analogues demands a prompt diagnosis and represents a significant therapeutic challenge in diabetic patients.

Adjuvanticity and Toxicity of Cobalt Oxide Nanoparticles as An Alternative Vaccine Adjuvant

There are very few adjuvants licensed for use in human vaccination, and alum-based adjuvants are the most widely used. Alum adjuvants predominantly boost Th2 immune responses and there is a need for new adjuvants that also stimulate Th1 immunity. We recently reported that cobalt oxide nanoparticles (Co(3)O(4)NPs) stimulate Th1-type immune responses in vivo. Here, we exploited this property to examine whether Co(3)O(4)NP could act as an adjuvant using the model antigen ovalbumin. Female C57BL/6 mice were immunized subcutaneously twice with ovalbumin plus adjuvant (Co(3)O(4)NPs or Imject® Alum) followed by intraperitoneal stimulation with soluble ovalbumin. Co(3)O(4)NPs induced a more balanced Th1- and Th2-type response, triggering higher specific Th1-dependent IgG2c production in addition to Th2-dependent IgG1 and less 'allergic' IgE production, and induced less inflammation at both the subcutaneous and intraperitoneal injection sites. Co(3)O(4)NPs could be a very useful adjuvant where both Th1 and Th2 responses are needed to clear pathogens.

Cutaneous Lesion Induced by a Subcutaneous Administration of Bortezomib

Introduction A 78-year-old man presented to our hospital with an indurated, painful lesion on the abdominal wall at the site of a recent subcutaneous (SC) bortezomib injection. The patient was diagnosed with multiple myeloma (MM) in 2007 after a bone marrow biopsy was done as part of anemia workup. He was started on melphalan and prednisone, which he successfully completed in December of 2007. He experienced a recurrence of MM in March of 2009 and was started on intravenous bortezomib and dexamethasone. In May of 2009, lenalidomide was substituted for bortezomib secondary to bortezomib-induced neuropathy. In January of 2010, his treatment was changed to thalidomide and dexamethasone secondary to lenalidomide-induced skin rash. Due to a favorable response, the treatment was discontinued in January of 2011. Secondary to new onset pancytopenia, a repeated bone marrow biopsy was performed in August of 2011, which confirmed the relapse of the MM. He was started on lenalidomide and dexamethasone orally, as well as bortezomib subcutaneously in August of 2011. After the first SC administration of bortezomib, the patient started to develop a small “boil” at the

Fluorescence Imaging of the Lymph Node Uptake of Proteins in Mice after Subcutaneous Injection: Molecular Weight Dependence

To use noninvasive fluorescence imaging to investigate the influence of molecular weight (MW) of proteins on the rate of loss from a subcutaneous (SC) injection site and subsequent uptake by the draining lymph nodes in mice. Bevacizumab (149kDa), bovine serum albumin (BSA, 66kDa), ovalbumin (44.3kDa) or VEGF-C156S (23kDa), labeled with the near infrared dye IRDye 680, were injected SC into the front footpad of SKH-1 mice. Whole body non-invasive fluorescence imaging was performed to quantitate the fluorescence signal at the injection site and in axillary lymph nodes. The half-life values, describing the times for 50% loss of proteins from the injection site, were 6.81h for bevacizumab, 2.85h for BSA, 1.57h for ovalbumin and 0.31h for VEGF-C156S. The corresponding axillary lymph node exposure, represented as the area of the % dose versus time curve, was 6.27, 5.13, 4.06 and 1.54% dose ∙ h, respectively. Our results indicate that the rate of loss of proteins from a SC injection site is inversely related to MW of proteins, while lymph node exposure is proportionally related to the MW of proteins in a mouse model.

Contribution of Endermology to Improving Indurations and Panniculitis/Lipoatrophy at Glatiramer Acetate Injection Site

Endermology is a mechanical massage therapy that enables fat mobilization and body contouring. The authors' aim was to assess the effect of endermology on indurations and panniculitis/lipoatrophy associated with subcutaneous administration of glatiramer acetate in patients with multiple sclerosis (MS). This was a multicenter pilot experience carried out in patients with MS treated with glatiramer acetate who showed indurations and/ or panniculitis/lipoatrophy at the injection site. Patients underwent endermology and glatiramer acetate treatment according to clinical practice. The primary endpoint was the change in indurations and/or panniculitis/lipoatrophy after 12 endermology sessions. Between April and July 2011, a total of 13 evaluable patients were included (mean age, 40.7±3.1 years; female, 100%; white, 100%; mean MS duration, 10.1±2.3 years; previous MS treatment, 46.2%; mean glatiramer acetate treatment duration, 27.3±9.5 months). Eleven patients (84.6%) showed local indurations (mean diameter, 3.4±0.5 cm; mean number, 9.0±1.0) and six patients (46.2%) areas of panniculitis/ lipoatrophy (mean number, 5.0±1.1). After 12 endermology sessions, patients with indurations reported having experienced a reduction in size (10 patients [90.9%]; mean diameter, 0.1±0.05 cm; P<0.001) and number of indurations (nine patients [81.8%]; mean number, 2.3±1.1; P<0.005). These indurations completely disappeared from arms, thighs, buttocks, and abdomen in six (75.0%), six (75.0%), two (50.0%), and three (42.9%) patients, respectively. Three of these patients (27.3%) recovered from all indurations. Although panniculitis/lipoatrophy did not completely disappear, all patients reported improvements. Most patients with indurations (63.6%) felt very satisfied and considered endermology very useful for reducing indurations. All patients with panniculitis/lipoatrophy were satisfied and considered to be endermology useful in improving it. In addition, endermology enabled glatiramer acetate tolerance to be improved in most patients (60.0%). Endermology may contribute to improving indurations and panniculitis/ lipoatrophy at the site of subcutaneous injection of glatiramer acetate in patients with MS, enabling areas of injection to recover, and treatment tolerance to increase.

Lymphatic Transport and Catabolism of Therapeutic Proteins after Subcutaneous Administration to Rats and Dogs

The mechanism underlying subcutaneous absorption of macromolecules and factors that can influence this process were studied in rats using PEGylated erythropoietins (EPOs) as model compounds. Using a thoracic lymph duct cannulation (LDC) model, we showed that PEGylated EPO was absorbed from the subcutaneous injection site mainly via the lymphatic system in rats, which is similar to previous reports in sheep. After subcutaneous administration, the serum exposure was reduced by ∼70% in LDC animals compared with that in the control animals, and most of the systemically available dose was recovered in the lymph. In both LDC and intact rats, the total radioactivity recoveries in excreta after subcutaneous administration were high (70-80%), indicating that catabolism, not poor absorption, was the main cause for the observed low bioavailability (30-40%). Moreover, catabolism of PEGylated EPO was found with both rat subcutaneous tissue homogenate and lymph node cell suspensions, and a significant amount of dose-related breakdown fragments was found in the lymph of LDC rats. In addition, the bioavailability of PEGylated EPOs was shown to be 2- to 4-fold lower in "fat rats," indicating that physiologic features pertinent to lymphatic transport can have a profound impact on subcutaneous absorption. Limited studies in dogs also suggested similar subcutaneous absorption mechanisms. Collectively, our results suggest that the lymphatic absorption mechanism for macromolecules is probably conserved among commonly used preclinical species, e.g., rats and dogs, and that mechanistic understanding of the subcutaneous absorption mechanism and associated determinants should be helpful in biologic drug discovery and development.

Abatacept in subjects who switch from intravenous to subcutaneous therapy: results from the phase IIIb ATTUNE study

ObjectiveTo assess safety, immunogenicity and efficacy in rheumatoid arthritis (RA) patients switched from long-term intravenous to subcutaneous (SC) abatacept.MethodsIn this phase IIIb, open-label, single-arm trial, patients who completed ≥4 years...

New insulins and insulin therapy

New insulins and insulin therapy

Tratamiento de las reacciones en el punto de la inyección en pacientes tratados con acetato de glatiramero

IntroductionGlatiramer acetate (GA) is an immunomodulatory drug, with an excellent safety profile, that is currently used for treatment of multiple sclerosis and is administered as daily subcutaneous injections. The most common adverse effects, which occur in approximately 20% to 60% of the patients, include pain, inflammation and induration at the injection sites (most of them transient), and panniculitis followed by localized lipoatrophy at the injection sites (50% of the patients), which is an adverse event common to other drugs administered subcutaneously. MethodsThis is a report of a pilot study carried out in MS patients treated with glatiramer acetate who showed indurations and/or panniculitis/lipoatrophy at the injection site. Patients underwent endermology and glatiramer acetate treatment according to clinical practice. The primary endpoint was the change in indurations and/or panniculitis/lipoatrophy after 12endermology sessions. ResultsBetween April 2011 and July 2011, a total of 13 evaluable patients were included. Eleven (84.6%) patients showed local indurations and areas of panniculitis/lipoatrophy. After 12 endermology sessions, patients with indurations reported having experienced a reduction in size and number of indurations. Even though panniculitis/lipoatrophy did not completely disappear, all patients reported it had improved. Additionally, endermology enabled glatiramer acetate tolerance to be improved in most patients (60.0%). ConclusionEndermology may contribute to improve indurations and panniculitis/lipoatrophy at the subcutaneous glatiramer acetate injection site of in MS patients, enabling areas of injection to be recovered, and to increase tolerance to treatment.

Pharmacokinetics (PK) and Pharmacodynamics (PD) of Subcutaneous Versus Intravenous Administration of Bortezomib in Patients with Relapsed Multiple Myeloma: Effects of Subcutaneous Injection Site and Concentration, and Patient Characteristics

Abstract 1863 Background:The proteasome inhibitor bortezomib is approved for the treatment of multiple myeloma (MM); the recommended dose and schedule is 1.3 mg/m2 administered by intravenous (IV) injection on days 1, 4, 8, and 11 of 21-day cycles. Findings from the phase 3 randomized, non-inferiority, MMY-3021 study (Moreau et al, Lancet Oncol 2011) demonstrated that subcutaneous (SC) administration of bortezomib, using the same dose and schedule, was feasible, and resulted in similar efficacy with an improved systemic safety profile (including significantly lower rates of peripheral neuropathy) versus IV bortezomib in patients with relapsed MM. These findings built upon an earlier randomized phase 1 study (CAN-1004; Moreau et al, Haematologica 2008). Here we present a comprehensive analysis of the PK and PD of SC versus IV bortezomib and evaluate the impact of SC administration site/concentration and patient characteristics, using all available data from MMY-3021 and CAN-1004, and pooled analyses. Methods:Patients with relapsed MM after 1–3 (MMY-3021) or ≥1 (CAN-1004) prior therapies were randomized to receive up to eight (or 10 for patients with late evolving response in MMY-3021) 21-day cycles of SC or IV bortezomib 1.3 mg/m2 on days 1, 4, 8, and 11. The SC injection concentration was 1 mg/mL in CAN-1004, but 2.5 mg/mL in MMY-3021, to reduce the volume injected. SC injection sites were the thighs and abdomen, and were rotated for successive injections. In both studies, the IV injection concentration was 1 mg/mL. In MMY-3021, 17/18 SC and 14/14 IV patients enrolled to the PK/PD substudy at selected sites were assessable; in CAN-1004, 10/12 patients on each arm were included in the PK/PD analyses. Blood samples were collected pre-dosing and at multiple time points post-dose on day 11 of cycle 1 for PK/PD analyses. Results:PK analyses demonstrated that bortezomib systemic exposure was equivalent with SC versus IV administration in MMY-3021 (AUClast: 155 vs 151 ng.hr/mL, geometric mean ratio of 0.992 [90% CI: 80.18, 122.80]) and comparable in CAN-1004 (AUClast: 195 vs 241 ng.hr/mL), although as would be expected, Cmax was lower (MMY-3021, 20.4 vs 223 ng/mL, Figure; CAN-1004, 22.5 vs 162 ng/mL) and Tmax was longer (both studies, 30 vs 2 mins; Figure). PD parameters of proteasome inhibition were also similar with SC versus IV bortezomib (Emax: MMY-3021, 63.7 vs 69.3%; CAN-1004, 57.0 vs 68.8%; AUE72hr: MMY-3021, 1714 vs 1383 %.hr; CAN-1004, 1619 vs 1283 %.hr), although time to Emax was longer (MMY-3021, 120 vs 5 mins; CAN-1004, 120 vs 3 mins). Analyses of PK and PD parameters in MMY-3021 according to SC injection site showed no differences (Table). Comparison of SC bortezomib PK and PD parameters between MMY-3021 and CAN-1004 showed that SC injection concentration (2.5 vs 1 mg/mL) had no appreciable effect. Demographic covariates had no impact on bortezomib systemic exposure based on pooled bortezomib PK parameters following SC injection in the two studies. Full results from subgroup analyses will be presented. Conclusions:Data from these randomized studies of SC versus IV bortezomib in patients with relapsed MM demonstrate that SC administration results in equivalent bortezomib plasma exposure, albeit with a lower Cmax and longer Tmax, compared with IV administration, together with comparable PD effects. SC injection site and concentration of the injected solution did not affect bortezomib PK and PD parameters, and the demographic covariates did not appear to have an impact on the PK and PD of SC bortezomib. The non-inferior efficacy of SC versus IV bortezomib in relapsed or refractory MM demonstrated in MMY-3021, together with the equivalent total systemic exposures (AUC) via the SC and IV routes of administration, support the use of bortezomib via the SC route across the settings of clinical use in which the safety and efficacy of IV bortezomib has been established.Mean (SD) bortezomib PK/PD parameters by injection sitePK by injection siteCmax(ng/mL)Tmax(hr)*AUClast(ng.hr/mL)Thigh (N = 11)17.7 (8.40)0.50 (0.08–1.00)171 (62.1)Abdomen (N = 6)25.4 (8.08)0.38 (0.25–1.00)127 (33.3)PD by injection siteEmax(%)Tmax(hr)*AUE72hr(%.hr)Thigh (N = 11)59.1 (6.37)2.00 (0.50–10)1700 (484)Abdomen (N = 6)72.3 (12.1)3.00 (1.00–24)1741 (863)*Median (range). [Display omitted] Disclosures:Moreau:Janssen: Advisory board, Honoraria; Millennium Pharmaceuticals, Inc.: Advisory board, Honoraria. Off Label Use: Bortezomib administered via subcutaneous injection. Hulin:Celgene: Honoraria; Janssen-Cilag: Honoraria. Leleu:Janssen: Insitutional grants and lecture fees. Esseltine:Millennium Pharmaceuticals, Inc.: Employment; Johnson & Johnson: Equity Ownership. Venkatakrishnan:Millennium Pharmaceuticals, Inc.: Employment. Skee:Janssen Research & Development: Employment. Feng:Janssen Research & Development: Employment. Girgis:Janssen Research & Development: Employment. Cakana:Janssen Research & Development: Employment. Deraedt:Janssen Research & Development: Employment; Johnson & Johnson: Equity Ownership. Facon:Janssen: Advisory committee, Speakers Bureau.

CD56(+)CD146(+) Cells in Normal Human Bone Marrow-Stroma Proliferated to Form Tumors in severe Combined Immunodeficiency Mice

Abstract 1328 Background and Aims:We reported that acute myelogenous leukemia blasts and chronic myelogenous leukemia cells converted to stromal myofibroblasts to create an environment for the proliferation of leukemic cells in vitro and in vivo. Recently, we also reported that myelogenous leukemia-derived myofibroblasts formed blastomas in non-obese diabetes severe combined immunodeficiency (NOD/SCID) mice, in which the CD56-positive cell-fraction was selectively proliferated (16th EHA). To ascertain whether normal human bone marrow-stroma-derived cells also behave like leukemia-derived cells, stromal cells were injected to NOD/SCID mice, and tumor-formation was observed. Materials and Methods:Bone marrow cells were collected from informed normal individuals, whose adherent cells were separated and were cultured for one month to eliminate monocyte/macrophage, vascular cell, and pericyte to prepare stromal myofibroblast-rich fraction. Cells were injected to NOD/SCID mice intra-venously, peritoneally, and subcutaneously (3 × 106/mice). When the tumor formation was observed or mice were dead, they were sacrificed and the engrafted cells were analyzed. Results and Discussion:Between at day 70 and 90 after injection mice were dead. Autopsy findings revealed tumor formation at subcutaneous injection sites, and cells were also infiltrated to the liver and ascitic fluid. These cells expressed CD56, CD146, and Nestin strongly, but not other lineage-specific markers including CD133; however, the ratio of CD56(+)CD146(+) fraction in the injected stromal cells was below 0.1%. When the tumor cells were cultured in vitro, they exhibited spindle-shaped appearance, and doubling time was 12 to 16 hours. They expressed c-Myc, Klf4, Nanog, Sox2, and other molecules that are expressed in an immature somatic stem cell. These observations indicate that CD56(+)CD146(+) cell-fraction in bone marrow-stroma is very immature and highly proliferative. We are now analyzing biological characteristics of this specific cell-fraction, and determining the contribution to normal hematopoiesis. Disclosures:No relevant conflicts of interest to declare.

Determination of the Maximum Tolerated Dose of Panobinostat in Combination with a 5-Day Schedule of Azacitidine in High-Risk Myelodysplastic Syndrome and Acute Myeloid Leukemia: Planned Interim Analysis of a Phase Ib/II Study

Abstract 1529 Background:The management options for patients with high-risk myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) who are not eligible for intensive chemotherapy remain limited. The combination of hypomethylating agent and deacetylase inhibitor (DACi) has been shown to be synergistic, both in terms of leukaemia cell killing and gene reactivation in vitro. Aim:To investigate the safety, tolerability and preliminary efficacy of combining the oral pan-DACi panobinostat (LBH589) with azacitidine in previously untreated MDS or AML, not fit for standard induction therapy. Methods:Phase Ib/II multi-center open label dose-escalation and expansion study. Inclusion criteria: untreated IPSS intermediate-2 or high risk MDS, or AML (marrow blasts ≥20%), not eligible for standard induction therapy. Patients received azacitidine 75 mg/m2 SC on days 1–5 of each 28-day cycle with 10, 20, 30 or 40mg panobinostat orally 3 days per week (M/W/F) for 7 doses per cycle commencing on day 5. The safety and tolerability of the combination was assessed. Results:This preliminary analysis includes 26 patients (M 17, F 9), median age 69 years (36–81). 18 AML patients had intermediate (11/18) or poor cytogenetic risk (7/18); 8 MDS patients with intermediate-2 (7/8) or high risk (1/8) IPSS. Patients were enrolled into panobinostat dose-escalation cohorts of 10mg (4 patients), 20mg (7), 30mg (6) or 40mg (6); and expansion study 30mg (3). All grade non-hematologic adverse events regardless of relatedness to study treatment (>10%) were: subcutaneous injection site redness or pain (57%), fatigue (48%), nausea (30%), anorexia (22%), diarrhoea (22%), dyspnoea (13%), fever (13%), hyperbilirubinemia (13%), hyperglycaemia (13%), hyponatremia (13%), leg oedema (13%) and light headedness (13%). There were no unexpected adverse events or drug reactions. The principal dose-limiting toxicity (DLT) was fatigue, as haematological toxicity was not considered dose-limiting. In the dose-escalation phase, the grade 3/4 DLTs were: panobinostat 10mg cohort (0/4 DLT), panobinostat 20mg cohort (1/7 DLT; grade 3 fatigue), panobinostat 30mg cohort (1/6 DLT; grade 3 fatigue), panobinostat 40mg (4/6 DLTs; all grade 3: fatigue (1), syncope (1), hyponatremia (1) and somnolence/reduced level of consciousness (1)). Therefore, in combination with the 5-day schedule of azacitidine, the maximum tolerated dose (MTD) of panobinostat was defined at 30mg; this dose level has been selected for expanded accrual. At present 10/26 patients (38%) remain on combination study therapy. The panobinostat dose has been reduced by one dose level in 5/26 patients (19%) due to fatigue; 3 patients from panobinostat 40mg cohort. In 16 patients taken off study, the most common cause was disease progression (9), infection (2), atrial fibrillation treated with panobinostat interacting medication (2), patient choice (2) and fatigue (1). The median number of treatment cycles initiated was 4 (1–16). Preliminary efficacy in 18 AML patients, 3 achieved PR, 7 SD, 7 PD and 1 death unrelated to disease or therapy. In 8 MDS patients, 2 achieved CR, 3 PR, 2 SD, and 1 not evaluable (withdrawal due to patient choice). After a median follow-up of 276 days, the median OS is 239 days (22–472). Conclusion:In previously untreated MDS/AML, panobinostat and azacitidine is well tolerated and preliminary assessments demonstrate clinical activity. The MTD was determined to be 30mg of panobinostat in combination with a 5-day azacitidine schedule of 75mg/m2 daily. Further evaluation of this combination with panobinostat 30mg dose is ongoing in the dose-expansion phase of the study. Disclosures:Mollee:Celgene: Membership on an entity’s Board of Directors or advisory committees. Gervasio:Novartis: Employment. Winiger:Novartis AG: Employee, Employment, Equity Ownership, Honoraria. Hönemann:Celgene Pty Ltd: Employment. Wei:Novartis: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Spencer:Novartis: Honoraria, Research Funding; Celgene: Honoraria, Research Funding.

Subcutaneous abatacept versus intravenous abatacept: A phase IIIb noninferiority study in patients with an inadequate response to methotrexate

ObjectiveTo compare the efficacy and safety of subcutaneous (SC) and intravenous (IV) abatacept.MethodsIn this phase IIIb double-blind, double-dummy, 6-month study, patients with rheumatoid arthritis (RA) and inadequate responses to methotrexate were randomized to receive 125 mg SC abatacept on days 1 and 8 and weekly thereafter (plus an IV loading dose [∼10 mg/kg] on day 1) or IV abatacept (∼10 mg/kg) on days 1, 15, and 29 and every 4 weeks thereafter. The primary end point for determining the noninferiority of SC abatacept to IV abatacept was the proportion of patients in each group meeting the American College of Rheumatology 20% improvement criteria (achieving an ACR20 response) at month 6. Other efficacy end points, immunogenicity, and safety were also assessed.ResultsOf 1,457 patients, 693 of 736 (94.2%) treated with SC abatacept and 676 of 721 (93.8%) treated with IV abatacept completed 6 months. At month 6, 76.0% (95% confidence interval 72.9, 79.2) of SC abatacept–treated patients versus 75.8% (95% confidence interval 72.6, 79.0) of IV abatacept–treated patients achieved an ACR20 response (estimated difference between groups 0.3% [95% confidence interval –4.2, 4.8]), confirming noninferiority of SC abatacept to IV abatacept. Onset and magnitude of ACR responses and disease activity and physical function improvements were comparable between the SC and IV abatacept–treated groups. The proportions of adverse events (AEs) and serious AEs over 6 months were 67.0% and 4.2%, respectively, in the SC abatacept–treated group and 65.2% and 4.9%, respectively, in the IV abatacept–treated group, with comparable frequencies of serious infections, malignancies, and autoimmune events between groups. SC injection site reactions (mostly mild) occurred in 19 SC abatacept (IV placebo)–treated patients (2.6%) and 18 IV abatacept (SC placebo)–treated patients (2.5%). Abatacept-induced antibodies occurred in 1.1% of SC abatacept–treated patients and 2.3% of IV abatacept–treated patients.ConclusionSC abatacept provides efficacy and safety comparable with that of IV abatacept, with low immunogenicity and high retention rates, consistent with the established IV abatacept profile. Rates of injection site reactions were low. SC abatacept will provide additional treatment options, such as an alternative route of administration, for patients with RA.

Evaluation of abatacept administered subcutaneously in adults with active rheumatoid arthritis: impact of withdrawal and reintroduction on immunogenicity, efficacy and safety (phase Iiib ALLOW study)

ObjectivesTo assess the effect of a temporary interruption in subcutaneous (SC) abatacept on immunogenicity, safety and efficacy in patients with active rheumatoid arthritis despite methotrexate in a phase III trial.MethodsFollowing...

Subcutaneous Absorption of Monoclonal Antibodies: Role of Dose, Site of Injection, and Injection Volume on Rituximab Pharmacokinetics in Rats

To determine the effect of dose, the anatomical site of injection, and the injection volume on subcutaneous absorption of rituximab in rats and to explore absorption mechanisms using pharmacokinetic modeling. Rituximab serum concentrations were measured following intravenous and subcutaneous administration at the back, abdomen, and foot of rats. Several pharmacokinetic models were developed that included linear and saturable absorption, and degradation and/or protective binding at the injection site. Rituximab exhibited linear kinetics following intravenous administration; however, bioavailability following subcutaneous injection was inversely related to the dose level. For the 1mg/kg dose, bioavailability was approximately 70% at all tested injection sites, with faster absorption from the foot (T(max) = 12h for foot vs. 4.6days for back). Bioavailability for the 10mg/kg dose was 44 and 31% for the abdomen and back sites and 18% for 40mg/kg injected at the back. A pharmacokinetic model that included binding as part of the absorption mechanism successfully captured the nonlinearities in rituximab absorption. The anatomical site of subcutaneous injection influences the rate of absorption and bioavailability of rituximab in rats. Saturable binding may be a major determinant of the nonlinear absorptive transport of monoclonal antibodies.

Safety of subcutaneous adrenaline as prophylaxis against acute adverse reactions to anti-venom serum in snakebite.

To study the safety of low dose subcutaneous adrenaline given as prophylaxis against acute adverse reactions to anti-venom serum (AVS) in patients bitten by snakes. Patients admitted with snakebite envenoming who satisfied inclusion criteria were given 0.25 ml of 1:1000 adrenaline subcutaneously immediately before administration of AVS. They were observed for adverse effects, and pulse and blood pressure (BP) were monitored. 51 patients [35 males, mean age 34.8 years (SD 14)] were included in the study. Adverse reactions to AVS occurred in 15 (29.4%) patients. There was one death from suspected cerebral haemorrhage, and 3 (5.9%) patients developed small haematomas at the subcutaneous injection site. There were no significant changes in mean pulse or BP following administration of subcutaneous adrenaline. Low dose subcutaneous adrenaline did not cause significant changes in pulse rate or BP. Although the death was unlikely to be directly related to subcutaneous adrenaline, we suggest further studies on the safety of this prophylactic treatment before its routine use.

Extraosseous Calcification in Chronic Renal Failure

To the Editor: In the February issue of the journal, Boccara et al described 2 cases of tissue calcifications: one patient with severe renal failure and another patient with end stage renal disease. Calcification of the cutis and subcutis appeared at the site of subcutaneous injections of calcium-containing heparin. Boccara et al states that this tissue calcification is caused by the calcium content of the administered medication. Extraosseous calcification in patients with end stage renal disease is a well-known phenomenon.1 Apart from uremia and hyperparathyroidism, high-dose vitamin D administration, obesity, hypercoagulable state, and a deficiency in inhibitors of vascular calcification, like fetuin-A or matrix gla protein, seem to be involved.2-6 In case of calcific uremic arteriolopathy (calciphylaxis), extravascular calcifications are common (Fig. 1). In the early nonulcerative stage of the disease, patients present with subcutaneous indurated plaques difficult to distinguish from cellulitis.7 A typical complication after subcutaneous injection or skin biopsy in patients with calciphylaxis is a rapid calcification of vessels and tissue, leading to thrombosis and a formation of tissue necrosis. We doubt that the rare cases of calcinosis cutis after calcium-containing heparin in patients with chronic kidney disease are attributed to the calcium content of the solution. In fact, in this population, there are possible more likely explanations for extraosseous calcification.FIGURE 1: Vascular (arrow) and extravascular (arrowhead) calcifications in a patient with calciphylaxis.Braun Niko, MD Kimmel Martin, MD Alscher M. Dominik, MD Department of Internal Medicine, Division of Nephrology, Robert-Bosch Hospital Stuttgart, Germany

Selected Case From the Arkadi M. Rywlin International Pathology Slide Seminar

A high-grade angiosarcoma with epithelioid features located in the buttock of an 87-year-old woman arose in an area of old, palpable fat necrosis at the site of several subcutaneous injections administered 20 years previously. The nature of the injected material is unknown, but is presumed to have been an iron compound. Two weeks before surgery, the buttock lesion started to enlarge and was excised. It consisted of 3 contiguous nodules of old, calcified fat necrosis associated with plentiful hemosiderin. One of the nodules was largely replaced by an angiosarcoma, which was invading the edges of the other 2 nodules. The patient died from wound sepsis 41 days postoperatively, with no clinically apparent metastases. Vaccination injection-site sarcomas are well known to occur in cats, whereas in humans, rare sarcomas associated with prostheses and foreign materials have been reported; however, human injection-site sarcomas are vanishingly rare. The Club members agreed with the diagnosis of angiosarcoma at an injection site, with the majority calling it an epithelioid angiosarcoma. Many accepted that the injected material was probably iron, but one cautioned about regarding the injections as the cause of the angiosarcoma.

Insulin: Potential Negative Consequences of Early Routine Use in Patients With Type 2 Diabetes

The lack of adequate insulin secretion characterizes all hyperglycemic states. When insulin action is normal, as in type 1 diabetes, there is a near total loss of insulin secretory function. In type 2 diabetes, the abnormalities in insulin secretion are multiple. One of the initial defects is a loss of the early phase of meal-stimulated insulin secretion. This is followed by an inability of the β-cell to increase insulin secretion sufficient to overcome hepatic and peripheral insulin resistance. Type 2 diabetes is characterized by a progressive decrease in both β-cell mass and secretory function so that, in most individuals, absolute insulin deficiency occurs in the late stages of the disease. It would seem logical that the ideal treatment for type 2 diabetes should be early and continuing insulin therapy. Unfortunately, there are several characteristics of insulin treatment and insulin action in type 2 diabetes that limit the usefulness of insulin treatment and that suggest that chronic insulin therapy is best used in the later stages of diabetes when there is an absolute deficiency of insulin. In normal physiology, β-cell insulin secretion is coupled immediately with changes in the plasma glucose level (1). The secretory response is rapid (within a minute or two), and because the half-life of insulin is ~5 min, there is little lag time in the glucose regulatory system. Endogenously secreted insulin goes via the portal vein to the liver, where 30–80% of it is either metabolized or used (2). The portal vein-to-peripheral arterial insulin ratio is ~2:1. The administration of insulin exogenously eliminates the rapid regulation of plasma glucose, since the insulin must be taken up slowly and without regulation from the subcutaneous injection site. The kinetics are determined by the nature of the injected insulin formulation. Additionally, as illustrated in Fig. 1, it is necessary …