Preclinical Development of MGC018, a Duocarmycin-based Antibody-drug Conjugate Targeting B7-H3 for Solid Cancer.

B7-H3, also referred to as CD276, is a member of the B7 family of immune regulatory proteins. B7-H3 is overexpressed on many solid cancers, including prostate cancer, renal cell carcinoma, melanoma, squamous cell carcinoma of the head and neck, non-small cell lung cancer, and breast cancer. Overexpression of B7-H3 is associated with disease severity, risk of recurrence and reduced survival. In this article, we report the preclinical development of MGC018, an antibody-drug conjugate targeted against B7-H3. MGC018 is comprised of the cleavable linker-duocarmycin payload, valine-citrulline-seco duocarmycin hydroxybenzamide azaindole (vc-seco-DUBA), conjugated to an anti-B7-H3 humanized IgG1/kappa mAb through reduced interchain disulfides, with an average drug-to-antibody ratio of approximately 2.7. MGC018 exhibited cytotoxicity toward B7-H3-positive human tumor cell lines, and exhibited bystander killing of target-negative tumor cells when cocultured with B7-H3-positive tumor cells. MGC018 displayed potent antitumor activity in preclinical tumor models of breast, ovarian, and lung cancer, as well as melanoma. In addition, antitumor activity was observed toward patient-derived xenograft models of breast, prostate, and head and neck cancer displaying heterogeneous expression of B7-H3. Importantly, MGC018 exhibited a favorable pharmacokinetic and safety profile in cynomolgus monkeys following repeat-dose administration. The antitumor activity observed preclinically with MGC018, together with the positive safety profile, provides evidence of a potentially favorable therapeutic index and supports the continued development of MGC018 for the treatment of solid cancers. GRAPHICAL ABSTRACT: http://mct.aacrjournals.org/content/molcanther/19/11/2235/F1.large.jpg.

Can near-infrared spectroscopy identify the severity of shock in trauma patients?

BACKGROUND: Our recent experimental study showed that peripheral muscle tissue oxygen saturation (StO2), determined noninvasively by near-infrared spectroscopy (NIRS), was more reliable than systemic hemodynamics or invasive oxygenation variables as an index of traumatic shock. The purpose of this study was to establish the normal range of thenar muscle StO2 in humans and the relationship between shock state and StO2 in trauma patients. METHODS: This was a prospective, nonrandomized, observational, descriptive study in normal human volunteers (n = 707) and patients admitted to the resuscitation area of our Level I trauma center (n = 150). To establish a normal StO2 range, an NIRS probe was applied to the thenar eminence of volunteers (normals). Subsequently, in a group of trauma patients, an NIRS probe was applied to the thenar eminence and data were collected and stored for offline analysis. StO2 monitoring was performed continuously and noninvasively, and values were recorded at 2-minute intervals. Five moribund trauma patients were excluded. Members of our trauma faculty, blinded to StO2 values, classified each patient into one of four groups (no shock, mild shock, moderate shock, and severe shock) using conventional physiologic parameters. RESULTS: Mean +/- SD thenar StO2 values for each group were as follows: normals, 87 +/- 6% (n = 707); no shock, 83 +/- 10% (n = 85); mild shock, 83 +/- 10% (n = 19); moderate shock, 80 +/- 12% (n = 14); and severe shock, 45 +/- 26% (n = 14). The thenar StO2 values clearly discriminated the normals or no shock patients and the patients with severe shock (p < 0.05). CONCLUSION: Decreased thenar muscle tissue oxygen saturation reflects the presence of severe hypoperfusion and near-infrared spectroscopy may be a novel method for rapidly and noninvasively assessing changes in tissue dysoxia.

The effect of antipyretic therapy upon outcomes in critically ill patients: a randomized, prospective study.

BACKGROUND: Despite the large body of evidence suggesting a beneficial role of fever in the host response, antipyretic therapy is commonly employed for febrile critically ill patients. Our objective was to evaluate the impact of antipyretic therapy strategies on the outcomes of critically ill patients. METHODS: Patients admitted to the Trauma Intensive Care Unit over a nine-month period were eligible for inclusion, except those with traumatic brain injury. Patients were randomized on day three of the ICU stay into aggressive or permissive groups. The aggressive group received acetaminophen 650 mg every 6 h for temperature of >38.5 degrees C and a cooling blanket was added for temperature of >39.5 degrees C. The permissive group received no treatment for temperature of >38.5 degrees C, but instead had treatment initiated at temperature of >40 degrees C, at which time acetaminophen and cooling blankets were used until temperature was <40 degrees C. Patient demographics, daily temperatures, systemic inflammatory response syndrome (SIRS) scores, multiple organ dysfunction syndrome (MODS) scores, and infections and complications were recorded. RESULTS: Between December, 2002 and September, 2003, 572 patients were screened, of whom 82 met criteria for enrollment. Forty-four patients were randomized to the aggressive group and 38 patients were randomized to the permissive group for a total of 961 and 751 ICU days, respectively. There were 131 infections in the aggressive group and 85 infections in the permissive group (4 +/- 6 vs. 3 +/- 2 infections per patient, p = 0.26). There were seven deaths in the aggressive group and only one death in the permissive group (p = 0.06, Fisher Exact Test). The study was stopped after the first interim analysis due to the mortality difference, related to the issues of waiver of consent and the mandate for minimal risk. CONCLUSIONS: Aggressively treating fever in critically ill patients may lead to a higher mortality rate.

Outcome of motorcycle riders at one year post-injury.

OBJECTIVE: There is little information about the long-term effects of injury on victims of motorcycle crashes. Following the repeal of the mandatory helmet law in Florida, we studied the impact of crashes on riders and their outcomes one year post-injury. SUBJECTS: All patients involved in a motorcycle crash over a six-month time period were assessed at one year post-injury. Demographic information, health status, motorcycle and helmet usage, and employability were surveyed. RESULTS: There were 94 patients evaluated at our center for the first six-month period following the repeal of the helmet law, where 50 (56%) were wearing a helmet at the time of injury. Of the 94, we were able to contact 45 (48%) at one-year follow up. Fourteen (31%) of those contacted were not wearing a helmet at the time of their crash. At one year post-injury, 23 (51%) reported physical deficits, while 39 (86%) were working. Only 12 (27%) were riding a motorcycle again, and 11 (92%) were wearing a helmet. CONCLUSIONS: Motorcycle riders at one year post-injury continue to experience physical deficits related to their accidents. There is a small percentage of riders that resume riding a motorcycle after injury. Being involved in a motorcycle accident has deterred the injured rider from riding a motorcycle again at one year post-injury.