Suction thrombectomy of a uterine carcinosarcoma tumor thrombus extending into the IVC and right atrium.

Uterine carcinosarcoma is a rare, aggressive tumor with several cases in the literature reporting cardiac tumor thrombus involvement. In this case report, we describe a 72-year-old female with a history of uterine carcinosarcoma, who presented with extensive thrombus in the Inferior Vena Cava (IVC) and right atrium. The patient underwent an aspiration thrombectomy which aided in intravascular debulking of the thrombus. Histopathological analysis of the thrombus revealed tumor thrombus. In cryptic cases of tumor thrombus, thrombectomy with histopathological analysis can help confirm the diagnosis of metastatic disease and help guide oncologic staging and further therapy.

Thrombotic Microangiopathy After Hematopoietic Stem Cell and Solid Organ Transplantation: A Review for Intensive Care Physicians.

Intensive care physicians may assume the primary care of patients with transplant-associated thrombotic microangiopathy (TA-TMA), an uncommon but potentially critical complication of hematopoietic stem cell transplants (HSCTs) and solid organ transplants. TA-TMA can have a dramatic presentation with multiple organ dysfunction syndrome (MODS) associated with high morbidity and mortality. The typical presenting clinical features are hemolytic anemia, thrombocytopenia, refractory hypertension, proteinuria and worsening renal failure. Intestinal involvement, with abdominal pain, nausea and vomiting, gastrointestinal bleeding, and ascites are also common. Cardiopulmonary involvement may develop from various causes including pulmonary arteriolar hypertension, pleural and pericardial effusions, and diffuse alveolar hemorrhage. Due to other often concurrent complications after HSCT, early diagnosis and effective management of TA-TMA may be challenging. Close collaboration between ICU and transplant physicians, along with other relevant specialists, is needed to best manage these patients. There are currently no approved therapies for the treatment of TA-TMA. Plasma exchange and rituximab are not recommended unless circulating factor H (CFH) antibodies or thrombotic thrombocytopenic purpura (TTP; ADAMTS activity < 10%) are diagnosed or highly suspected. The role of the complement pathway activation in the pathophysiology of TA-TMA has led to the successful use of targeted complement inhibitors, such as eculizumab. However, the relatively larger studies using eculizumab have been mostly conducted in the pediatric population with limited data on the adult population. This review is focused on the role of intensive care physicians to emphasize the clinical approach to patients with suspected TA-TMA and to discuss diagnosis and treatment strategies.

Effect of post-pyloric Dobhoff tube retention during gastrojejunostomy for reduction of fluoroscopic time and radiation dose.

The purpose of this study was to determine whether retention of a post-pyloric Dobhoff tube (DHT) in position to serve as a visual guide through the pylorus during gastrojejunostomy (GJ) tube placement results in a reduction in fluoroscopy time, procedure time, and estimated radiation dose. A retrospective study evaluated patients who underwent GJ tube placement or gastric to GJ conversion from January 1, 2017, to April 1, 2021. Demographic and procedural data were collected, and results were evaluated using descriptive statistics and hypothesis testing through an unpaired Student's t-test. Of the 71 GJ tube placements included for analysis, 12 patients underwent placement with a post-pyloric DHT in position, and 59 patients underwent placement without a post-pyloric DHT in position. The mean fluoroscopy time and estimated radiation dose were significantly reduced in patients who underwent GJ tube placement with a post-pyloric DHT in position compared with those without (7.08 min vs. 11.02 min, P = 0.004; 123.12 mGy vs. 255.19 mGy, P = 0.015, respectively). The mean total procedure time was also reduced in patients who underwent GJ tube placement with a post-pyloric DHT in position compared with those who had no post-pyloric DHT, but this finding lacked statistical significance (18.55 min vs. 23.15 min; P = 0.09). Post-pyloric DHT retention can be utilized during GJ tube placement to reduce radiation exposure to both the patient and interventionalist.

Nocturnal hypoglycemia in type 1 and type 2 diabetes: an update on prevalence, prevention, pathophysiology and patient awareness.

INTRODUCTION: Despite considerable progress in diabetes treatment, prevalence of nocturnal hypoglycemia in type 1 diabetes mellitus (T1DM) and advanced insulin treated type 2 diabetes mellitus (T2DM) remains high. AREAS COVERED: The present manuscript describes the prevalence of night-time hypoglycemia as reported in observational and randomized controlled trials. Factors that affect the risk of hypoglycemia are highlighted. The authors also describe impaired awareness of hypoglycemia and available preventive methods. EXPERT OPINION: Prevention of nocturnal hypoglycemia includes behavioral, dietary and pharmacologic interventions. The most recent development with the lowest rate of hypoglycemia is sensor-augmented pumps with predictive low glucose suspend technology. These pumps combine continuous subcutaneous insulin infusion with continuous glucose monitoring and use various algorithms to predict and stop hypoglycemia before it develops.

Using DPP-4 inhibitors to modulate beta cell function in type 1 diabetes and in the treatment of diabetic kidney disease.

INTRODUCTION: DPP-4 inhibitors have pleomorphic effects that extend beyond the anti-hyperglycemic labeled use of the drug. DPP-4 inhibitors have demonstrated promising renal protective effects in T2DM and T1DM and protective effects against immune destruction of pancreatic beta-cells in T1DM. AREAS COVERED: The efficacy of DPP-4 inhibitors in the treatment of diabetic kidney disease and possible adjunct with insulin in the treatment of T1DM to preserve beta-cell function. Pertinent literature was identified through Medline, PubMed and ClinicalTrials.gov (1997-November 2018) using the search terms T1DM, sitagliptin, vildagliptin, linagliptin, beta-cell function, diabetic nephropathy. Only articles are written in the English language, and clinical trials evaluating human subjects were used. EXPERT OPINION: DPP-4 inhibitors can be used safely in patients with diabetic kidney disease and do not appear to exacerbate existing diabetic nephropathy. Linagliptin reduces albuminuria and protects renal endothelium from the deleterious effects of hyperglycemia. The effects of DPP-4 inhibitors on preserving beta-cell function in certain subtypes of T1DM [e.g. Latent Autoimmune Diabetes in Adult (LADA) and Slowly Progressive Type 1 Diabetes (SPIDDM)] are encouraging and show promise.

Development of a Target cell-Biologics-Effector cell (TBE) complex-based cell killing model to characterize target cell depletion by T cell redirecting bispecific agents.

T-cell redirecting bispecific antibodies (bsAbs) or antibody-derived agents that combine tumor antigen recognition with CD3-mediated T cell recruitment are highly potent tumor-killing molecules. Despite the tremendous progress achieved in the last decade, development of such bsAbs still faces many challenges. This work aimed to develop a mechanism-based pharmacokinetic/pharmacodynamic (PK/PD) modeling framework that can be used to assist the development of T-cell redirecting bsAbs. A Target cell-Biologics-Effector cell (TBE) complex-based cell killing model was developed using in vitro and in vivo data, which incorporates information on binding affinities of bsAbs to CD3 and target receptors, expression levels of CD3 and target receptors, concentrations of effector and target cells, as well as respective physiological parameters. This TBE model can simultaneously evaluate the effect of multiple system-specific and drug-specific factors on the T-cell redirecting bsAb exposure-response relationship on a physiological basis; it reasonably captured multiple reported in vitro cytotoxicity data, and successfully predicted the effect of some key factors on in vitro cytotoxicity assays and the efficacious dose of blinatumomab in humans. The mechanistic nature of this model uniquely positions it as a knowledge-based platform that can be readily expanded to guide target selection, drug design, candidate selection and clinical dosing regimen projection, and thus support the overall discovery and development of T-cell redirecting bsAbs.

Pharmacokinetics and Exposure Response Relationships of Ustekinumab in Patients With Crohn's Disease.

BACKGROUND & AIMS: Ustekinumab is a monoclonal antibody that binds with high affinity to the p40 subunit of human interleukin 12 (IL12 and IL23) that has been approved for treatment of patients with moderate to severe Crohn's disease (CD). However, there are few data on its pharmacokinetic properties or the relationship between drug exposure levels and patient response. We collected data from 2 Phase 3 induction studies and 1 maintenance study to determine ustekinumab's pharmacokinetic features, relationship between exposure and response, and optimal serum concentrations for efficacy. METHODS: We collected data on serum concentrations of ustekinumab and efficacy from induction studies of patients with moderate to severe CD given ustekinumab for 8 weeks following a single intravenous dose (either 130 mg or approximately 6 mg/kg). We collected the same data from a maintenance study of patients with a response to ustekinumab in the induction study who then received subcutaneous injections (90 mg) every 8 or 12 weeks for 44 weeks. At week 44 of the maintenance study (52 weeks after treatment began), patients were evaluated for the primary endpoint of clinical remission (defined as a CD activity index score below 150 points), endoscopic markers of efficacy, and serum level of C-reactive protein. Ustekinumab concentration data were categorized into quartiles and relationships between exposure and response were assessed. Optimal concentration cutoff values were evaluated using receiver operating characteristic curve analysis. RESULTS: Serum concentrations of ustekinumab over time were proportional to dose and did not differ significantly between the induction studies. In the maintenance study, ustekinumab concentration reached the steady state by the second maintenance dose; the median trough concentration was approximately threefold higher in patients given ustekinumab at 8-week intervals compared with 12-week intervals. Ustekinumab serum concentrations associated with rates of clinical remission and endoscopic efficacy endpoints, correlated inversely with level of C-reactive protein, and did not associate with use of immunomodulators. Trough concentrations of ustekinumab of 0.8 (or even up to 1.4 µg/mL) or greater were associated with maintenance of clinical remission in a higher proportion of patients than patients with lower trough concentrations. CONCLUSIONS: In an analysis of data from Phase 3 studies of patients with moderate to severe CD, we found serum concentrations of ustekinumab to be proportional to dose and associate with treatment efficacy. Concentrations of ustekinumab did not seem to be affected by cotreatment with immunomodulators. Clinicaltrials.gov no. NCT01369329 (UNITI 1), NCT01369342 (UNITI 2), and NCT01369355 (IM-UNITI).

Modification of the Fc Region of a Human Anti-oncostatin M Monoclonal Antibody for Higher Affinity to FcRn Receptor and Extension of Half-life in Cynomolgus Monkeys.

The purpose of this study was to evaluate the pharmacokinetics (PK) of anti-oncostatin M (OSM) IgG1 monoclonal antibodies, CNTO 1119 and its Fc variant (CNTO 8212), which incorporates the LS(Xtend) mutation to extend terminal half-life (T1/2 ), after a single intravenous (IV) or subcutaneous (SC) administration in cynomolgus monkeys, and to predict human PK. In study 1, single doses of CNTO 1119 and CNTO 8212 were administered IV or SC at 3 mg/kg to cynomolgus monkeys (n = 3 per group). In study 2, single doses of CNTO 8212 were administered IV at 1, 5 or 20 mg/kg, or SC at 5 mg/kg to cynomolgus monkeys (n = 5 per group). Serial blood samples were collected for assessment of serum concentrations of CNTO 1119 and/or CNTO 8212. A two-compartment population PK model with first-order elimination was utilized to simultaneously describe the serum concentrations of CNTO 1119 and CNTO 8212 over time after IV and SC administration in cynomolgus monkeys. The typical population PK parameter estimates for CNTO 1119 in cynomolgus monkeys were clearance (CL) = 2.81 mL/day/kg, volume of distribution of central compartment (V1 ) = 31.3 mL/kg, volume of distribution of peripheral compartment (V2 ) = 23.3 mL/kg, absolute bioavailability (F) = 0.84 and T1/2 = 13.4 days. In comparison, the typical population PK parameter estimates for CNTO 8212 in cynomolgus monkeys were CL = 1.41 mL/day/kg, V1 = 39.8 mL/kg, V2 = 32.6 mL/kg, F = 0.75 and T1/2 = 35.7 days. The mean CL of CNTO 8212 was ~50% lower compared with that for CNTO 1119 in cynomolgus monkeys. The overall volume of distribution (V1 +V2 ) for CNTO 8212 was about 32% larger compared with that for CNTO 1119, but generally similar to the vascular volume in cynomolgus monkeys. The T1/2 of CNTO 8212 was significantly (p < 0.05) longer by about 2.7-fold than that for CNTO 1119 in cynomolgus monkeys. Thus, the modification of the Fc portion of an anti-OSM IgG1 mAb for higher FcRn binding affinity resulted in lower systemic clearance and a longer terminal half-life in cynomolgus monkeys. CNTO 8212 demonstrated linear PK after a single IV dose (1-20 mg/kg) in cynomolgus monkeys. The predicted human PK parameters suggest that CNTO 8212 is likely to exhibit slow clearance and long terminal half-life in human beings and may likely allow less frequent dosing in the clinical setting.

Pharmacokinetics and Exposure-response Relationship of Golimumab in Patients with Moderately-to-Severely Active Ulcerative Colitis: Results from Phase 2/3 PURSUIT Induction and Maintenance Studies.

BACKGROUND AND AIMS: To assess golimumab pharmacokinetics [PK] and exposure-response [ER] in adults with moderate-to-severe ulcerative colitis [UC] from the Program of Ulcerative Colitis Research Studies Utilizing an Investigational Treatment [PURSUIT] studies. METHODS: We analysed golimumab PK and ER data of patients with moderate-to-severe UC from the PURSUIT-subcutaneous induction [N = 1064] and maintenance [N = 464] studies. Induction analyses evaluated serum golimumab concentration [SGC] and efficacy data through Week [wk] 6 following subcutaneous doses at wk0 and wk2; maintenance analyses assessed data through wk54 following 4-weekly dosing. ER relationships were assessed using trend, logistic regression, and receiver-operating-characteristic curve analyses. RESULTS: Median SGCs peaked at induction wk2 for golimumab 100/50mg, 200/100mg, and 400/200mg. Wk6 median SGCs were 0.78, 1.78, and 4.01 µg/ml, respectively. SGCs were sustained, reaching steady state approximately 8wks after golimumab maintenance commenced [wk14 of golimumab] regardless of induction dose. Median trough SGCs from maintenance wks8-44 ranged from 0.69 to 0.83 µg/ml [50 mg] and 1.33-1.58 µg/ml [100 mg]. SGCs were approximately dose proportional, and higher SGCs were associated with higher efficacy response rates during induction and maintenance. Factors associated with golimumab exposure were body weight, antibody-to-golimumab status, serum albumin, alkaline phosphatase, faecal markers, C-reactive protein, and pancolitis. SGCs of 2.5 µg/ml [induction wk6] and 1.4 µg/ml [maintenance steady-state trough] are potential target concentrations. Immunomodulators had no apparent impact on SGC with golimumab 100mg, whereas drug levels were slightly higher with golimumab 50mg with vs without immunomodulators. CONCLUSIONS: SGCs are approximately dose proportional, and a positive SGC-efficacy relationship exists during induction/maintenance golimumab treatment of adult UC patients. Optimal SGC targets require validation in prospective studies.

First-in-human study to assess guselkumab (anti-IL-23 mAb) pharmacokinetics/safety in healthy subjects and patients with moderate-to-severe psoriasis.

PURPOSE: The purpose of this study is to evaluate the pharmacokinetics, immunogenicity, safety, and tolerability of guselkumab, a human monoclonal antibody with high affinity and specificity for binding to interleukin-23. METHODS: In this first-in-human, phase 1, randomized study, a single intravenous (IV; 0.03-10 mg/kg) or subcutaneous (SC; 10-300 mg) dose of guselkumab was administered to 47 healthy subjects, and a single SC dose (placebo, 10, 30, 100, 300 mg) was administered to 24 patients with moderate-to-severe psoriasis. RESULTS: Mean maximum observed serum concentration and area under the zero-to-infinity serum concentration-time curve of guselkumab increased in an approximately dose-proportional manner over the dose range of 0.03-10 mg/kg following a single IV administration or 10-300 mg following a single SC administration. Mean clearance and volume of distribution ranged from 3.62-6.03 mL/day/kg and 99.38-123.22 mL/kg, respectively. Mean half-life ranged from 12 to 19 days in healthy subjects and patients with psoriasis. Among guselkumab-treated subjects/patients, 1/30 (3.3 %) healthy subjects in the IV group, 0/6 healthy subjects in the SC group, and 1/20 (5.0 %) patients with psoriasis tested positive for antibodies to guselkumab. No clinically significant adverse events were identified in this study. CONCLUSION: Guselkumab pharmacokinetic profiles were generally comparable between healthy subjects and patients with psoriasis. Guselkumab, administered as an IV infusion or SC injection, was well tolerated in healthy subjects and patients with psoriasis.

Evaluation of disease-mediated therapeutic protein-drug interactions between an anti-interleukin-6 monoclonal antibody (sirukumab) and cytochrome P450 activities in a phase 1 study in patients with rheumatoid arthritis using a cocktail approach.

This therapeutic protein-drug interaction study evaluated the disease-mediated effect of sirukumab (anti-interleukin 6 [anti-IL-6] monoclonal antibody) on the pharmacokinetics of the cytochrome P450 (CYP) probe substrates midazolam (CYP3A), omeprazole (CYP2C19), warfarin (CYP2C9), and caffeine (CYP1A2) in patients with active rheumatoid arthritis (RA). Twelve patients with C-reactive protein (CRP) ≥ 8.0 mg/L at screening received oral administration of a CYP probe cocktail consisting of 0.03 mg/kg midazolam, 10 mg warfarin + 10 mg vitamin K (equivalent to 5 mg S-warfarin), 20 mg omeprazole, and 100 mg caffeine 1 week before and 1, 3, and 6 weeks after a single subcutaneous dose of 300 mg sirukumab. The results showed that the pharmacokinetics of midazolam, omeprazole, and S-warfarin were nonequivalent before and after the administration of a single dose of 300 mg sirukumab. Area under the plasma concentration-time curve (AUC0- ∞ ) for midazolam, omeprazole, and S-warfarin was reduced by 30%-35%, 37%-45%, and 18%-19%, respectively, after sirukumab administration. Caffeine AUC0-∞ was increased by 20%-34% after sirukumab administration. The effect of sirukumab on CYP substrates was sustained for at least 6 weeks. No new adverse drug reactions related to the administration of sirukumab were observed in this study. These results suggest that sirukumab may reverse IL-6-mediated suppression of CYP3A, CYP2C9, and CYP2C19 activities in patients with active RA.

Pharmacokinetics and immunogenicity investigation of a human anti-interleukin-17 monoclonal antibody in non-naïve cynomolgus monkeys.

The pharmacokinetics (PK) of biologic therapeutics, especially monoclonal antibodies (mAbs), in monkeys generally presents the most relevant predictive PK information for humans. However, human mAbs, xenogeneic proteins to monkeys, are likely to be immunogenic. Monkeys previously treated with a human mAb (non-naïve) may have developed antidrug antibodies (ADAs) that cross-react with another test mAb in subsequent studies. Unlike PK studies for small-molecule therapeutics, in which animals may be reused, naïve monkeys have been used almost exclusively for preclinical PK studies of biologic therapeutics to avoid potential pre-existing immunologic cross-reactivity issues. The propensity and extent of pre-existing ADAs have not been systematically investigated to date. In this study, the PK and immunogenicity of mAb A, a human anti-human interkeukin-17 mAb, were investigated in a colony of 31 cynomolgus monkeys previously exposed to other human mAbs against different targets. We screened the monkeys for pre-existing antibodies to mAb A prior to the PK study and showed that 44% of the monkeys had pre-existing cross-reactive antibodies to mAb A, which could affect the PK characterization of the antibody. In the subcolony of monkeys without measurable pre-existing ADAs, PK and immunogenicity of mAb A were successfully characterized. The impact of ADAs on mAb A PK was also demonstrated in the monkeys with pre-existing ADAs. Here we report the results and propose a pragmatic approach for the use of non-naïve monkeys when conducting PK studies of biologic therapeutics.

Dose selection of siltuximab for multicentric Castleman's disease.

PURPOSE: Siltuximab is a monoclonal antibody that binds to interleukin (IL)-6 with high affinity and specificity; C-reactive protein (CRP) is an acute-phase protein induced by IL-6. CRP suppression is an indirect measurement of IL-6 activity. Here, modeling and simulation of the pharmacokinetic (PK)/pharmacodynamic (PD) relationship between siltuximab and CRP were used to support dose selection for multicentric Castleman's disease (CD). METHODS: PK/PD modeling was applied to explore the relationship between siltuximab PK and CRP suppression following intravenous siltuximab infusion in 47 patients with B cell non-Hodgkin's lymphoma (n = 17), multiple myeloma (n = 13), or CD (n = 17). Siltuximab was administered as 2.8, 5.5, or 11 mg/kg q2wks, 11 mg/kg q3wks, or 5.5 mg/kg weekly. Simulations of studied or hypothetical siltuximab dosage regimens (15 mg/kg q4wks) were also performed to evaluate maintenance of CRP suppression below the cutoff value of 1 mg/L. RESULTS: A two-compartment PK model and an inhibitory indirect response PD model adequately described the serum siltuximab and CRP concentration-time profiles simultaneously. PD parameter estimates were physiologically plausible. For all disease types, simulations showed that 11 mg/kg q3wks or 15 mg/kg q4wks would reduce serum CRP to below 1 mg/L after the second dose and throughout the treatment period. CONCLUSIONS: PK/PD modeling was used to select doses for further development of siltuximab in multicentric CD. The dosing recommendation was also supported by the observed efficacy dose-response relationship. CRP suppression in the subsequent randomized multicentric CD study was in agreement with the modeling predictions.

Non-Clinical Pharmacokinetics, Prediction of Human Pharmacokinetics and First-in-Human Dose Selection for CNTO 5825, an Anti-Interleukin-13 Monoclonal Antibody.

CNTO 5825 is a human anti-interleukin-13 (IL-13) monoclonal antibody (mAb) that inhibits binding of human IL-13 to IL-13Rα1 and IL-13Rα2. The purpose of this investigation was to predict human pharmacokinetics (PK) of CNTO 5825 using different allometric approaches and non-clinical PK data in order to select the right and safe doses for first-in-human (FIH) study. After intravenous (IV) administration of CNTO 5825, clearance (CL) ranged from 9.98 to 11.49 ml/day/kg in rats and from 5.78 to 7.19 ml/day/kg in cynomolgus monkeys. The volume of distribution at steady-state (Vss) in rats was large (151.52-155.64 ml/kg) compared to cynomolgus monkey (49.77-61.10 ml/kg). The terminal half-life (T1/2 ) ranged from 12.29 to 14.15 days in rats and from 6.61 to 7.73 days in cynomolgus monkeys. The PK of CNTO 5825 was linear in 1-10 mg/kg dose range in both species. The bioavailability after subcutaneous (SC) administration was 94% and 79% in rats and cynomolgus monkeys, respectively. The predicted CL and Vss based on allometric methods and PK data from rats and monkeys were within twofold of observed CL and Vss in human beings; the predicted CL and Vss in human beings (70 kg) based on time-invariant method with combined PK data from rats and monkeys were 4.84 ± 1.13 ml/day/kg and 68.93 ± 35.55 ml/kg, respectively. The selected doses for the FIH study based on time-invariant method and no observed adverse effect level in toxicity studies in rats and monkeys provided exposures that were subsequently shown to be well tolerated and safe in human beings.

Clinical impact of concomitant immunomodulators on biologic therapy: Pharmacokinetics, immunogenicity, efficacy and safety.

Immune-mediated inflammatory diseases encompass a variety of different clinical syndromes, manifesting as either common diseases such as rheumatoid arthritis (RA), inflammatory bowel disease (IBD) and psoriasis, or rare diseases such as cryopyrin-associated periodic syndromes. The therapy for these diseases often involves the use of a wide range of drugs including nonsteroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, immunomodulators, and biologic therapies. Due to the abundance of relevant clinical data, this article provides a general overview on the clinical impact of the concomitant use of immunomodulators and biologic therapies, with a focus on anti-tumor necrosis factor-α agents (anti-TNFα), for the treatment of RA and Crohn's disease (CD). Compared to biologic monotherapy, concomitant use of immunomodulators (methotrexate, azathioprine, and 6-mercaptopurine) often increases the systemic exposure of the anti-TNFα agent and decreases the formation of antibodies to the anti-TNFα agent, consequently enhancing clinical efficacy. Nevertheless, long-term combination therapy with immunomodulators and anti-TNFα agents may be associated with increased risks of serious infections and malignancies. Therefore, the determination whether combination therapy is suitable for a patient should always be based on an individualized benefit-risk evaluation. More research should be undertaken to identify and validate prognostic markers for predicting patients who would benefit the most and those who are at greater risk from combination therapy with immunomodulators and anti-TNFα agents.

Pharmacokinetic bridging approach for developing biologics-delivery devices: a case study with a golimumab autoinjector.

PURPOSE: This Phase 1 pharmacokinetic (PK) comparability study in healthy subjects was performed to compare the PK properties and tolerability of single-dose golimumab 100 mg delivered subcutaneously by an autoinjector device or by a standard needle and syringe that had been used for the subcutaneous (SC) delivery of golimumab in pivotal Phase 3 studies. METHODS: Healthy male subjects were randomly assigned to receive a single injection of SC golimumab 100 mg using either the autoinjector or a standard needle and syringe. The PK parameters of golimumab were calculated using noncompartmental analysis. An ANOVA model was applied to compare the 2 injection methods with regard to golimumab C(max) and the AUC from 0 and 49 days after administration (AUC(0-49d)). FINDINGS: In the prespecified evaluable PK population (n = 141), the mean (SD) values for C(max) were 6.6 (3.3) and 6.0 (3.0) µg/mL, and AUC(0-49d) values were 97.4 (43.2) and 88.9 (36.8) µg·d/mL in the autoinjector and needle/syringe groups, respectively. The 90% CI of the geometric mean ratios of the AUC(0-49d) values between the 2 delivery methods was 95.17% to 120.55%; the 90% CI of the geometric mean ratio of C(max) was 96.14% to 127.42%. In a post hoc intent-to-treat analysis using data from all 156 subjects, the 90% CIs of both C(max) and AUC(0-49d) fell within the prespecified range for bioequivalence (80% to 125%). The prevalences of adverse events were similar between the 2 groups. IMPLICATIONS: The totality of the study findings suggests that the PK properties and tolerability of SC administration of golimumab by the 2 delivery methods were comparable. The study results successfully bridged the container-closure change from a liquid-in-vial product to either a prefilled syringe or an autoinjector with the same liquid formulation.

Association between serum concentration of infliximab and efficacy in adult patients with ulcerative colitis.

BACKGROUND & AIMS: We analyzed data collected during the Active Ulcerative Colitis Trials (ACT-1 and ACT-2) to assess relationships between serum concentrations of infliximab and outcomes of adults with moderate-to-severe ulcerative colitis. METHODS: We compared serum concentrations of infliximab with outcomes of 728 patients with moderately-to-severely active ulcerative colitis who participated in ACT-1 or ACT-2; efficacy data were collected at weeks 8, 30, and 54 (for ACT-1 only). Relationships between serum concentration of infliximab and efficacy outcomes were assessed using trend, logistic regression, and receiver operating characteristic curve analyses. We also evaluated factors that affected the relationship between exposure and response. RESULTS: Median serum concentrations of infliximab at weeks 8, 30, and/or 54 were significantly higher in patients with clinical response, mucosal healing, and/or clinical remission than in patients who did not meet these response criteria. There were statistically significant relationships between quartile of infliximab serum concentration and efficacy at these time points (P < .01). Infliximab therapy was effective for a smaller proportion of patients in the lowest quartile, and these patients had lower serum levels of albumin and a higher incidence of antibodies to infliximab than patients in other quartiles. Although the relationship between exposure to infliximab and response varied among patients, approximate serum concentrations of 41 µg/mL infliximab at week 8 of induction therapy and 3.7 µg/mL at steady-state during maintenance therapy produced optimal outcomes in patients. CONCLUSIONS: Serum concentrations of infliximab are associated with efficacy in patients with moderate-to-severe ulcerative colitis; however, complex factors determine the relationship between exposure to this drug and response. A prospective evaluation of the value of measuring serum concentrations of infliximab should be performed before these data can be included in patient management strategies. Clinicaltrials.gov numbers: NCT00036439 and NCT00096655.

A novel approach to evaluate the pharmacokinetic biocomparability of a monoclonal antibody derived from two different cell lines using simultaneous crossover design.

A parallel study design with a large number of subjects has been a typical path for pharmacokinetic (PK) biocomparability assessment of biotherapeutics with long half-lives and immunogenic propensity, for example, monoclonal antibodies (mAb). A recently published innovative bioanalytical method that can quantify mAb produced from two different cell lines in the same sample opened an avenue to exploring a simultaneous crossover study design for PK biocomparability assessment of biotherapeutics. Siltuximab, a chimeric IgG1 mAb-targeting interleukin-6, was studied as an example. The pharmacokinetic biocomparability of siltuximab derived from mouse myeloma (Sp2/0) cells and Chinese hamster ovary cells was previously assessed and demonstrated in a clinical PK biocomparability study that enrolled more than 140 healthy subjects using a parallel trial design. The biocomparability was successfully shown in six cynomolgus monkeys in a preclinical proof-of-concept study using the new crossover study design supported by the analytical method. The impact of antidrug antibodies on the assessment of biocomparability was minimal. This novel approach opened up a new arena for the evaluation of PK biocomparability of biotherapeutics with unique molecular signatures such as a mAb derived from different cell lines.

Mechanistic pharmacokinetic/target engagement/pharmacodynamic (PK/TE/PD) modeling in deciphering interplay between a monoclonal antibody and its soluble target in cynomolgus monkeys.

For therapeutic monoclonal antibodies (mAbs) against soluble ligands, the free ligand level can, theoretically, be used as a surrogate for efficacy. However, it can be extremely challenging technically to measure free ligand level in the presence of an excessive amount of antibody-ligand complex. The interplay among such mAbs, ligands, and the downstream pharmacodynamic (PD) effects has not been well defined. Using siltuximab and interleukin-6 (IL-6) as model compounds, a pharmacokinetic (PK)/target engagement (TE) model was established via simultaneous fitting of total siltuximab, total IL-6, and free IL-6 concentration profiles following a low dose of siltuximab in cynomolgus monkeys. The model adequately captured the observed data and provided estimation of model parameters with good precision. The PK/TE model was used to predict free IL-6 profiles at higher siltuximab doses, where the accurate determination of free IL-6 concentration became technically too difficult. The measured free IL-6 levels from the low-dose groups and PK/TE model-predicted free IL-6 levels from the high-dose groups were used to drive an indirect response TE/PD model to describe the concentration-effect relationship between free IL-6 and C-reactive protein (CRP). The TE/PD model adequately captured both CRP elevation and CRP suppression in response to free IL-6 concentration change from baseline with a linear stimulation function, providing direct evidence that the PK/TE model-predicted free IL-6 levels from the high-dose groups were accurate. Overall, the results provided an integrated PK/TE/PD modeling and bioanalytical framework for prediction of efficacious dose levels and duration of action for mAbs against soluble ligands with rapid turnover.