129 Development of AB-201, a novel allogeneic anti-HER2-specific CAR-NK cell therapy for the treatment of HER2+ tumors

Background

Human Epidermal Growth Factor Receptor 2 (HER2), is a receptor tyrosine kinase that is highly expressed on the surface of many solid tumors. While many patients derive meaningful benefit from the approved HER2-directed therapies, most will eventually suffer relapse or progression of their disease highlighting the need for additional treatment options. Currently there are no FDA-approved cellular therapies targeting HER2. Over the past decade, however, cellular therapy has been shown to be a viable treatment option in different cancer types. Here we present AB-201, an off-the-shelf, cryopreserved cord blood (CB)-derived HER2 chimeric antigen receptor (CAR)-natural killer (NK) cell therapy as a safe, active, and readily available option for patients with HER2+ solid tumors.

Methods

AB-201 is comprised of ex vivo expanded allogeneic CB-derived NK cells that have been genetically modified to express a HER2-directed CAR and presented as a cryopreserved infusion-ready product. The manufacturing process utilizes a feeder-cell line engineered to express factors specifically identified as supportive to NK cell expansion and a lentiviral transduction step to introduce the HER2 CAR construct. In vitro characterization of AB-201 included evaluation of the purity and expression of cell surface markers by flow cytometry and short- (4 hour) and long-term (over 5 days) cytotoxicity assays in the presence of HER2+ tumor cell lines at various effector to target ratios. In addition, AB-201 efficacy was assessed in vivo in established ovarian (intraperitoneal, SKOV-3), breast (intraperitoneal, HCC1954) and gastric (subcutaneous, N87) xenograft models in NSG mice.

Results

HER2 CAR expression was detected in 93.1% of AB-201 cells. AB-201 is 97.9% CD3-/CD56+ cells and 94.6% CD56+/CD16+. Further characterization of AB-201 demonstrated high expression of NK activating receptors such as NKG2D, NKp30, NKp46, and DNAM-1 and expression of the chemokine receptor, CXCR3. AB-201 demonstrated concentration-dependent and HER2 targeted short-term cytotoxic activity and sustained long-term cell killing against the tumor cell lines SKOV-3, HCC1954, and NCI-N87. Efficacy, as evidenced by a significant reduction in bioluminescent signal or tumor volume, was observed in all xenograft models. A significant survival benefit over non-transduced NK cells or trastuzumab controls was demonstrated in the HCC1954 model.

Conclusions

Data presented herein suggests that AB-201, a highly pure and readily expandable HER2-directed CAR NK cell product, has potential to be an effective therapy in the treatment of HER2+ tumors.

Ethics Approval

The animal studies were conducted in accordance with an Institutional Animal Care and Use Committee-approved protocol and with the approval of an IACUC committee at each center where the studies took place

Implementation and adoption of advanced care planning in the elderly trauma patient

Background

Geriatric trauma has high morbidity and mortality, often requiring extensive hospital stays and interventions. The number of geriatric trauma patients is also increasing significantly and accounts for a large proportion of trauma care. Specific geriatric trauma protocols exist to improve care for this complex patient population, who often have various comorbidities, pre-existing medications, and extensive injury within a trauma perspective. These guidelines for geriatric trauma care often suggest early advanced care planning (ACP) discussions and documentation to guide patient and family-centered care.

Methods

A provincial ACP program was implemented in April of 2012, which has since been used by our level 1 trauma center. We applied a before and after study design to assess the documentation of goals of care in elderly trauma patients following implementation of the standardized provincial ACP tool on April 1, 2012.

Results

Documentation of ACP in elderly major trauma patients following the implementation of this tool increased significantly from 16 to 35%. Additionally, secondary outcomes demonstrated that many more patients received goals of care documentation within 24 h of admission, and 93% of patients had goals of care documented prior to intensive care unit (ICU) admission. The number of trauma patients that were admitted to the ICU also decreased from 17 to 5%.

Conclusion

Early advanced care planning is crucial for geriatric trauma patients to improve patient and family-centered care. Here, we have outlined our approach with modest improvements in goals of care documentation for our geriatric population at a level 1 trauma center. We also outline the benefits and drawbacks of this approach and identify the areas for improvement to support improved patient-centered care for the injured geriatric patient. Here, we have provided a framework for others to implement and further develop.

Electronic supplementary material

The online version of this article (10.1186/s13017-018-0201-6) contains supplementary material, which is available to authorized users.

Optimization of Large-Scale Expansion and Cryopreservation of Human Natural Killer Cells for Anti-Tumor Therapy

Allogeneic natural killer (NK) cell therapy is a potential therapeutic approach for a variety of solid tumors. We established an expansion method for large-scale production of highly purified and functionally active NK cells, as well as a freezing medium for the expanded NK cells. In the present study, we assessed the effect of cryopreservation on the expanded NK cells in regards to viability, phenotype, and anti-tumor activity. NK cells were enormously expanded (about 15,000-fold expansion) with high viability and purity by stimulating CD3⁺ T cell-depleted peripheral blood mononuclear cells (PBMCs) with irradiated autologous PBMCs in the presence of IL-2 and OKT3 for 3 weeks. Cell viability was slightly reduced after freezing and thawing, but cytotoxicity and cytokine secretion were not significantly different. In a xenograft mouse model of hepatocellular carcinoma cells, cryopreserved NK cells had slightly lower anti-tumor efficacy than freshly expanded NK cells, but this was overcome by a 2-fold increased dose of cryopreserved NK cells. In vivo antibody-dependent cell cytotoxicity (ADCC) activity of cryopreserved NK cells was also demonstrated in a SCID mouse model injected with Raji cells with rituximab co-administration. Therefore, we demonstrated that expanded/frozen NK cells maintain viability, phenotype, and anti-tumor activity immediately after thawing, indicating that expanded/frozen NK cells can provide ‘ready-to-use’ cell therapy for cancer patients.

Different Stroke Volumes for the Left and Right Ventricles in the Moving-Actuator Type Total Artificial Heart

A new electromechanical moving-actuator type total artificial heart (TAH) has been developed to solve the imbalance problem without an extra compliance chamber. A different stroke volume was achieved by the large left sac size and the asymmetry of the actuator motion referred to the center position. The left ventricle consists of a double sac with the outer sac attached to the actuator providing active diastolic filling, while the double sac of the right ventricle being free from the actuator, and having sufficient suction produced due to the rigid pump housing. The stroke volume difference between the left and right sac is compensated through the air in the interventricular space of the variable volume (VV) space. Computer simulation based on the geometrical relationships between the blood sacs and the actuator was performed to simulate the physical mechanisms of the moving-actuator type TAH. Results were then compared with the measured pressure changes in various chambers of the pump and the stroke volume differences in mock circulation test. In two acute calf experiments, the balanced left and right atrial pressures were achieved in the moving-actuator type TAH without an extra compliance chamber

Phase I Study of Random Healthy Donor-Derived Allogeneic Natural Killer Cell Therapy in Patients with Malignant Lymphoma or Advanced Solid Tumors

Natural killer (NK) cells with mismatched killer cell immunoglobulin-like receptor-ligand pairs have shown efficacy and been proven safe in treatment of cancer patients. Ex vivo-expanded and highly activated NK cells (MG4101) had been generated under good manufacturing practice conditions, which demonstrated potent anticancer activity in vitro and in vivo in preclinical studies. The current phase I clinical trial was designed to evaluate safety and possible clinical efficacy of repetitive administrations of MG4101 derived from random unrelated healthy donors into patients with malignant lymphoma or advanced, recurrent solid tumors. The maximum dose (3 × 10(7) cells/kg, triple infusion) was tolerable without significant adverse events. Of 17 evaluable patients, 8 patients (47.1%) showed stable disease and 9 (52.9%) showed progressive disease. We also evaluated the capacity of MG4101 to influence host immune responses. Administration of MG4101 augmented NKG2D expression on CD8(+) T cells and upregulated chemokines that recruit T cells. In contrast, administration of MG4101 reduced regulatory T cells and myeloid-derived suppressor cells and suppressed TGFβ production. In conclusion, administration of a large number of MG4101 cells was not only safe and feasible, but also exhibited efficacy in maintaining the effector arm of the host immune response.

Effects of vitamin d on blood pressure and endothelial function

Vitamin D deficiency is prevalent, primarily due to limited sun exposure, which may be observed in urban areas, or as a result of modern lifestyles. Common myths about vitamin D persist, including that it is mostly obtained from the diet and is only essential for bone and mineral homeostasis. Nonetheless, advances in biomedical science suggest that vitamin D is a hormone that is integral to numerous physiologic functions in most cells and tissues. Therefore, abnormal vitamin D levels may contribute to health disturbances. A number of recent reports on potential associations between vitamin D deficiency and cardiovascular disease have highlighted its role in this system. A focus over the previous decade has been to better understand the mechanisms behind vitamin D regulation and the pathophysiology associated with suboptimal vitamin D levels. Vitamin D deficiency is highly associated with the incidence of cardiovascular diseases, even when considering other well-known risk factors. In this process, the renin-angiotensin system is disrupted, and hypertension and endothelial dysfunction contribute to the risk of cardiovascular disease. Likewise, clinical outcomes upon the normalization of vitamin D levels have been investigated in different patient populations. It makes sense that vitamin D supplementation to improve vitamin D status among vitamin D-deficient individuals could be useful without requiring a sudden lifestyle change. This manuscript provides a brief overview of vitamin D metabolism and the vitamin D receptor. It also summarizes the current clinical research relating to vitamin D supplementation and its effects on hypertension and endothelial dysfunction in cardiovascular medicine.

Transdisciplinary research for complex One Health issues: a scoping review of key concepts

In order to address the complexity inherent in researching One Health (OH) issues, we support the concept that researchers must transcend individual disciplinary and non-disciplinary boundaries, and move into the realm of transdisciplinary (TD) research approaches. For the purposes of this paper we use the term OH and the concept that OH research is conducted to solve complex health challenges at the animal-human--human-ecosystem interface. TD goes beyond interdisciplinary research to engages disciplines and communities through a unified conceptual framework. In this scoping review we investigated key concepts, definitions and themes in OH and TD based on the peer reviewed literature. We identified nine emerging themes in TD research: (1) education, (2) conflict amongst disciplines, (3) effective communication, (4) shared conceptual framework, (5) leadership, (6) perceived power differentials, (7) community-based methodologies, (8) support for TD research and (9) time and effort. This review provides a synthesized knowledge base that describes the nature, extent of evidence and challenges of engaging in TD initiatives. This knowledge base further provides a foundation for those interested in developing improved strategies for TD collaborative and cross-sectoral research in OH.

GMP-compliant, large-scale expanded allogeneic natural killer cells have potent cytolytic activity against cancer cells in vitro and in vivo

Ex vivo-expanded, allogeneic natural killer (NK) cells can be used for the treatment of various types of cancer. In allogeneic NK cell therapy, NK cells from healthy donors must be expanded in order to obtain a sufficient number of highly purified, activated NK cells. In the present study, we established a simplified and efficient method for the large-scale expansion and activation of NK cells from healthy donors under good manufacturing practice (GMP) conditions. After a single step of magnetic depletion of CD3(+) T cells, the depleted peripheral blood mononuclear cells (PBMCs) were stimulated and expanded with irradiated autologous PBMCs in the presence of OKT3 and IL-2 for 14 days, resulting in a highly pure population of CD3(-)CD16(+)CD56(+) NK cells which is desired for allogeneic purpose. Compared with freshly isolated NK cells, these expanded NK cells showed robust cytokine production and potent cytolytic activity against various cancer cell lines. Of note, expanded NK cells selectively killed cancer cells without demonstrating cytotoxicity against allogeneic non-tumor cells in coculture assays. The anti-tumor activity of expanded human NK cells was examined in SCID mice injected with human lymphoma cells. In this model, expanded NK cells efficiently controlled lymphoma progression. In conclusion, allogeneic NK cells were efficiently expanded in a GMP-compliant facility and demonstrated potent anti-tumor activity both in vitro and in vivo.

SU-E-J-01: Analysis of Acquisition Parameters That Caused Artifacts in Four-Dimensional (4D) CT Images of Targets Undergoing Regular Motion

PURPOSE

The aim of this study was to clarify the impacts of acquisition parameters on artifacts in four-dimensional computed tomography (4D CT) images, such as the partial volume effect (PVE), partial projection effect (PPE), and mis-matching of initial motion phases between adjacent beds (MMimph) in cine mode scanning.

METHODS

A thoracic phantom and two cylindrical phantoms (2 cm diameter and heights of 0.5 cm for No. 1 and 10 cm for No.2) were scanned using 4D CT. For the thoracic phantom, acquisition was started automatically in the first scan with 5 sec and 8 sec of gantry rotation, thereby allowing a different phase at the initial projection of each bed. In the second scan, the initial projection at each bed was manually synchronized with the inhalation phase to minimize the MMimph. The third scan was intentionally un-synchronized with the inhalation phase. In the cylindrical phantom scan, one bed (2 cm) and three beds (6 cm) were used for 2 and 6 sec motion periods. Measured target volume to true volume ratios (MsTrueV) were computed. The relationships among MMimph, MsTrueV, and velocity were investigated.

RESULTS

In the thoracic phantom, shorter gantry rotation provided more precise volume and was highly correlated with velocity when MMimph was minimal. MMimph reduced the correlation. For moving cylinder No. 1, MsTrueV was correlated with velocity, but the larger MMimph for 2 sec of motion removed the correlation. The volume of No. 2 was similar to the static volume due to the small PVE, PPE, and MMimph.

CONCLUSIONS

Smaller target velocity and faster gantry rotation resulted in a more accurate volume description. The MMimph was the main parameter weakening the correlation between MsTrueV and velocity. Without reducing the MMimph, controlling target velocity and gantry rotation will not guarantee accurate image presentation given current 4D CT technology.

Endogenous factors affecting oxidative stability of beef loin, pork loin, and chicken breast and thigh meats

The susceptibility of meats from different animal species (chicken breast [CB] and thigh [CT], pork [PL and beef [BL]) to lipid oxidation was studied. The amounts of TBARS in raw PL, CB, and CT did not change during a 7-d storage period. TBARS values of raw BL, however, significantly increased during 7-d storage because of high heme iron content, high lipoxygenase-like activities, and low 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities. Ferric ion reducing capacities (FRC) were detected in all raw meats, but their characteristics were different: storage-unstable in CB and CT and storage-stable in PL and BL. Ferric ion reducing capacities in raw CB and CT was higher than those of PL and BL, and could be related to their high oxidative stability. The TBARS values of cooked meat increased significantly with storage. The rates of TBARS increase in cooked CT and BL were significantly higher than those of cooked CB and PL after a 7-d storage. Nonheme iron content in cooked BL was higher than other meats and increased significantly after 7 d. Cooked BL had a higher amount of heat-stable FRC, which acted as a prooxidant in the presence of high free ionic irons, than other meats. Therefore, high heat-stable FRC and increased nonheme iron content in cooked BL were responsible for its high susceptibility to lipid oxidation. Despite relatively low nonheme iron and heat-stable FRC levels, cooked CT showed similar levels of TBARS to cooked BL after a 7-d storage because of its high PUFA content.

A Review of Critical Differences among Loop, Thiazide, and Thiazide-Like Diuretics

Diuretics are a drug class with heterogeneous assortments. This article reviews general pharmacologic mechanisms and clinical implications of loop, thiazide, and thiazide-like diuretics.

Loop diuretics act in the loop of Henle by blocking the sodium-potassium-chloride (Na+-K+-2Cl-) symport. They are effective in relieving congestive symptoms and edematous signs of heart failure. Activation of the neurohormonal system and subsequent pathologic myocardial remodeling limit the use of loop diuretics unless fluid balance is not met to relieve patients' symptoms with life-saving pharmacologic modalities. Adverse effects on electrolyte balance may cause life-threatening consequences. The combination of K+-sparing diuretics or angiotensin-converting enzyme inhibitors with loop diuretics may not only prevent life-threatening complications caused by electrolyte imbalance, but also may delay progression of the disease with proven mortality benefit. Recent findings of worsening renal function and higher mortality rate with the use of oral and intravenous loop diuretics further demands appropriate use of these drugs.

Thiazide diuretics and thiazide-like diuretics act in the distal convoluted tubule by blocking Na+-Cl- symport. Thiazide diuretics reduce cardiovascular mortality by achieving target blood pressure in patients with hypertension. Compared with other antihypertensive drugs, thiazide diuretics have less desirable metabolic effects. However, it has not yet been shown that the negative metabolic effects of these drugs are associated with negative mortality and morbidity. Based on the need for a multidrug regimen to reach target blood pressure in most patients with hypertension, thiazide diuretics may be used in addition to a drug or drugs without metabolic complications.

Phase I trial of neoadjuvant concurrent chemoradiotherapy with S-1 and weekly irinotecan in locally advanced rectal cancer

14543

Background: S-1 is a novel, orally administered 5-FU analogue and is known of radiosensitizer. The aim of this study was to establish the feasibility and efficacy of S-1 in combination with weekly irionotecan with concurrent pelvic radiotherapy (RT) in patients with locally advanced rectal cancer. Methods: Clinical stage T3–4 or N+(on MRI) rectal adenocarcinoma patients received weekly irinotecan 40mg/m2(day1,8,15,22,29) and S-1 at dose levels of 40, 50, 60 and 70mg/m2 (5days a week from day 1 to 38) according to phase I methodology. Concurrently conventional RT was given at daily fractions of 1.8 Gy on 5 days a week for a total dose of 50.4 (45 + 5.4)Gy. Surgery was performed 4–8 weeks following completion of chemoradiation. Results: A total 16 patients (10M/7F, median age 46 years, ECOG PS0–1) were enrolled between August 2005 and July 2006. One pt withdrew the consent during CCRT. Dose-limiting toxicity (DLT) occurred at 50mg/m2 of S-1 in one of six pts (G4 cerebral infarction). At dose of 60, 70mg/m2 of S-1, no DLT occurred. G3/4 toxicties were rare. Fifthteen pts underwent surgery and R0 resection was achieved in 13 pts. Four pts (25.0%) had a pathological complete response. Conclusions: The recommended dose (RD) for further study is S-1 70mg/m2 with irinotecan and radiotherapy. Neoadjuvant S-1/irinotecan/RT is feasible and well tolerated. Phase II trial is being conducted.

No significant financial relationships to disclose.

Electrocardiographic and Blood Pressure Effects of the Ephedra-Containing TrimSpa Thermogenic Herbal Compound in Healthy Volunteers

STUDY OBJECTIVE

To determine the effect of an ephedra-containing thermogenic herbal compound (TrimSpa) on rate-corrected QT (QTc) interval duration and systolic blood pressure.

DESIGN

Randomized, double-blind, placebo-controlled, crossover, intent-to-treat study.

SETTING

Student laboratory at a college of pharmacy.

SUBJECTS

Thirteen healthy volunteers (eight men, five women).

INTERVENTION

Participants were given TrimSpa, which contains more than 30 ingredients including ephedra 15 mg and caffeine 60 mg, or matching placebo 3 times/day for 7 days in a crossover fashion with a 7-day washout period between treatments.

MEASUREMENTS AND MAIN RESULTS

Each subject's QTc interval and systolic blood pressure were measured on days 1, 4, and 7. These measurements were performed immediately before study drug ingestion (baseline) and 0.5, 1, and 3 hours after ingestion. No differences in these variables were found between the TrimSpa and placebo groups. In one subject taking TrimSpa, the QTc interval increased 96 msec from baseline, more than double the largest increase in the placebo group.

CONCLUSION

Standard doses of TrimSpa did not induce changes in subjects' QTc intervals or systolic blood pressures. However, because the QTc interval dramatically changed in one subject taking TrimSpa, a large study is needed to determine if the effect is an artifact or if the subject represents a subset of people for whom the drug may pose a risk.

An evaluation of the impact of oral magnesium lactate on the corrected QT interval of patients receiving sotalol or dofetilide to prevent atrial or ventricular tachyarrhythmia recurrence

BACKGROUND

Intravenous magnesium reduces the QTc interval of patients receiving ibutilide. Whether oral magnesium can reduce the QTc interval associated with oral sotalol and dofetilide is not known. This study was undertaken to evaluate the impact of oral magnesium on the QTc interval and whether an inherent intracellular magnesium deficiency exists among patients with arrhythmias.

METHODS

Participants receiving sotalol or dofetilide for atrial or ventricular arrhythmias were randomized to receive magnesium l-lactate (504 mg elemental magnesium daily, Niche Pharmaceuticals, Roanoke, TX) or placebo for 48 hours. A 12-lead electrocardiogram (ECG) was obtained at baseline, 3 hours, and 51 hours after dosing to correspond to the Tmax after oral ingestion. The QTc interval was measured from the ECGs and compared between groups. Intracellular magnesium concentrations were determined by energy-dispersive x-ray analysis at baseline and 51 hours after dosing (Intracellular Diagnostics, Inc., Foster City, CA).

RESULTS

The QTc interval reductions from baseline were greater in the magnesium group than placebo at 3 and 51 hours (P = 0.015 and P < 0.001, respectively). Sixty-three percent of patients (regardless of experimental group) had baseline intracellular magnesium concentrations below the normal reference range of 33.9-41.9 mEq/IU, with an average level of 32.6 +/- 2.2 mEq/IU.

CONCLUSIONS

Oral magnesium l-lactate raises intracellular magnesium concentrations and lowers the QTc interval of patients receiving sotalol or dofetilide.

Absence of QTc-Interval-Prolonging or Hemodynamic Effects of a Single Dose of Bitter-Orange Extract in Healthy Subjects

STUDY OBJECTIVE

To evaluate the hemodynamic and electrocardiographic effects of a single dose of commercially available bitter-orange dried-fruit extract, which is increasingly being used in dietary supplements.

DESIGN

Randomized, double-blind, placebo-controlled, crossover study.

SETTING

University of Connecticut, Storrs Campus.

SUBJECTS

Eighteen healthy volunteers aged 18 years or older.

INTERVENTION

Subjects were given either placebo or bitter-orange dried-fruit extract (450 mg standardized to 27 mg of m- or p-synephrine) in phase 1. The opposite treatment was given during phase 2 after a washout period of at least 7 days.

MEASUREMENTS AND MAIN RESULTS

The rate-corrected QT (QTc) interval and blood pressure were measured before dosing and at 1, 3, 5, and 8 hours after dosing. Mean+/-SD values of the maximum postdose values were compared between groups. Subjects receiving bitter-orange extract versus those receiving placebo had similar postdose QTc intervals (402+/-29 vs 403+/-24 msec, p=0.653), systolic blood pressure (114+/-10 vs 115+/-8 mm Hg, p=0.686) and diastolic blood pressure (68+/-9 vs 68+/-8, p=0.879).

CONCLUSION

Bitter-orange dried-fruit extract standardized to m- or p-synephrine 27 mg did not significantly alter the QTc interval or blood pressure after a single dose was administered. Future studies are necessary to ensure the safety of this herbal product with multiple doses.

The impact of catecholamines in patients with or without beta-blockers on the ventricular fibrillation cycle length and ventricular fibrillation cycle length variability

OBJECTIVES

To evaluate the impact of epinephrine, norepinephrine, or placebo on the ventricular fibrillation cycle length (VFCL) and the variability of VFCL (cvVFCL) measurements in implantable cardioverter defibrillator (ICD) patients with or without beta-blockers.

METHODS

Forty-three patients scheduled for their 6-week post-ICD placement noninvasive electrophysiologic study were included in the study at the Arrhythmia Procedure Laboratory at Hartford Hospital, Hartford, CT. This randomized, double-blind, placebo-controlled evaluation was approved by the Hartford Hospital Institutional Review Board.

RESULTS

After 2 seconds of continuous VF, 7 consecutive VFCLs were measured from the ICD device recording printout using a 0.5 mm scale ruler under magnification at baseline and after the infusion of catecholamines (epinephrine or norepinephrine at 2 mcg/min) or matching placebo at steady state. The average VFCL and the cvVFCL were determined for each study phase. Subgroup analysis based on chronic beta-blocker use was performed. No between-group differences were noted for epinephrine, norepinephrine, or placebo group for baseline (P=0.538) or postinfusion VFCL (P=0.749) or for baseline (P=0.561) or postinfusion cvVFCL (P=0.623) Regardless of catecholamine group randomization, longer pre- and postinfusion VFCL were noted in those receiving beta-blockers (P=0.157, P=0.019) but no differences in cvVFCL were noted (P=0.216, P=0.474) versus those without beta-blockers, respectively.

CONCLUSION

Moderately dosed epinephrine or norepinephrine does not affect either VFCL or the variability of VFCL after short duration of ventricular fibrillation. Chronic cardioselective beta-blockade prolongs VFCL without any impact on coefficient of variation of VFCL.

Electrocardiographic effects of an Ephedra-Free, multicomponent weight-loss supplement in healthy volunteers

STUDY OBJECTIVE

Metabolife 356, an ephedra-containing weight-loss product, substantially increases the corrected QT (QTc) interval. Metabolife Ephedra Free, a similar supplement, contains caffeine and extracts of green tea, garcinia cambogia, and yerba mate. Its electrocardiographic (ECG) effects are not known. Therefore, we sought to determine the effect of this supplement on the QTc interval.

DESIGN

Randomized, double-blind, placebo-controlled, crossover study.

SETTING

University of Connecticut, Storrs Campus.

SUBJECTS

Twenty healthy volunteers. Intervention. A single capsule containing half the normal recommended dose of Metabolife Ephedra Free or matching placebo was administered in crossover fashion, with a 7-day washout period between treatments.

MEASUREMENTS AND MAIN RESULTS

Baseline and three postdose ECG measurements were obtained, and QTc intervals were measured over a 5-hour study period. No significant differences in the QTc interval or other ECG variables were observed between the Metabolife Ephedra Free and placebo groups.

CONCLUSION

At half the recommended single dose, Metabolife Ephedra Free does not affect the QTc interval or other ECG variables over 5 hours. Dose-response studies and studies of longer duration should be conducted.

Hemodynamic impact of an ephedra-free multicomponent weight-loss supplement

PURPOSE

The effect of Metabolife Ephedra-Free on blood pressure (BP) and hemodynamics was studied.

METHODS

Healthy volunteers were randomly assigned to take a single dose of Metabolife Ephedra-Free or matching placebo and then crossed over to the opposite treatment after a seven-day washout period. BP was measured at baseline and one, three, and five hours after administration. Cardiac index, systemic vascular resistance index (SVRI), and total thoracic fluid content were determined in a subgroup of subjects.

RESULTS

Twenty patients (mean +/- S.D. age, 24.8 +/- 1.9 years) completed the study. No significant differences in systolic or diastolic BP were found between the Metabolife Ephedra-Free and placebo groups. In the subgroup (n = 8), SVRI was higher (but not significantly so) in the Metabolife Ephedra-Free group than in the placebo group at one hour (2162.5 +/- 421.1 versus 1934.6 +/- 344.2 dyn x sec x cm(-5) x m(2)); the difference was significant at five hours (1981.6 +/- 293.3 versus 1765.1 +/- 340.3 dyn x sec x cm(-5) x m(2)).

CONCLUSION

Single doses of Metabolife Ephedra-Free did not affect BP in healthy young volunteers. SVRI did not exceed the normal range but was elevated at five hours compared with SVRI in placebo recipients.