Safety and efficacy of quavonlimab, a novel anti-CTLA-4 antibody (MK-1308), in combination with pembrolizumab in first-line advanced non-small-cell lung cancer

BACKGROUND

Quavonlimab (MK-1308), a novel anti-CTLA-4 antibody, in combination with pembrolizumab was investigated in a phase I study.

PATIENTS AND METHODS

Dose-escalation (DE) phase: patients with advanced/metastatic solid tumors received an initial flat dose of quavonlimab as monotherapy [25 mg (cohort 1), 75 mg (cohort 2), or 200 mg (cohort 3)] followed by four treatments of the same quavonlimab dose plus pembrolizumab every 3 weeks (Q3W). Dose-confirmation phase (DC): patients with stage IIIB/IV non-small-cell lung cancer (NSCLC) received first-line quavonlimab [25 mg Q3W (arm A), 25 mg Q6W (arm B), 75 mg Q6W (arm C), or 75 mg Q3W (arm E)] plus pembrolizumab. Primary objectives were safety and tolerability and establishment of the recommended phase II dose (RP2D) of quavonlimab when used with pembrolizumab. Objective response rate (ORR) was a secondary endpoint. Efficacy based on PD-L1 expression, tumor mutational burden (TMB), and changes in circulating CD4+/CD8+ cells were exploratory endpoints.

RESULTS

Thirty-nine patients were enrolled in DE [n = 14 (cohort 1); n = 17 (cohort 2); n = 8 (cohort 3)] and 134 in DC [n = 40 (arm A); n = 40 (arm B); n = 40 (arm C); n = 14 (arm E)]. Maximum-tolerated dose was not reached. Grade 3-5 treatment-related adverse events (AEs; graded according to NCI CTCAE v4.03) occurred in 0%, 23.5%, and 75.0% of patients in DE cohorts 1, 2, and 3, respectively, and 35.0%, 30.0%, 35.0%, and 57.1% of patients in DC arms A, B, C, and E, respectively. Efficacy was observed at all dose levels/schedules in patients with NSCLC. ORRs were 40.0% [95% confidence interval (CI), 24.9-56.7; arm A], 37.5% (95% CI, 22.7-54.2; arm B), 27.5% (95% CI, 14.6-43.9; arm C), and 35.7% (95% CI, 12.8-64.9; arm E). PD-L1 expression and total number of circulating CD4+ cells correlated with ORR.

CONCLUSIONS

Quavonlimab 25 mg Q6W plus pembrolizumab demonstrated similar efficacy and a better safety profile among all quavonlimab doses/schedules evaluated; this regimen was the chosen RP2D.

Weak magnetic fields alter stem cell-mediated growth

Biological systems are constantly exposed to electromagnetic fields (EMFs) in the form of natural geomagnetic fields and EMFs emitted from technology. While strong magnetic fields are known to change chemical reaction rates and free radical concentrations, the debate remains about whether static weak magnetic fields (WMFs; <1 mT) also produce biological effects. Using the planarian regeneration model, we show that WMFs altered stem cell proliferation and subsequent differentiation via changes in reactive oxygen species (ROS) accumulation and downstream heat shock protein 70 (Hsp70) expression. These data reveal that on the basis of field strength, WMF exposure can increase or decrease new tissue formation in vivo, suggesting WMFs as a potential therapeutic tool to manipulate mitotic activity.

Evaluation of the tourniquet test as a predictor of diabetic retinopathy

Medical practitioners often have difficulty in assessing the presence or severity of diabetic retinopathy. The tourniquet test is a method of assessing diabetic capillary fragility that has been felt to reliably correlate with background and proliferative diabetic retinopathy. We studied 100 consecutive diabetic patients and 50 age-matched controls in a masked fashion, using fundus photographs and fluorescein angiography to correlate the amount of capillary fragility with the presence and severity of background and proliferative diabetic retinopathy. Although the severity of diabetic capillary fragility did correlate with the presence and severity of diabetic retinopathy (p less than 0.001), this test was not as good an indicator of diabetic retinopathy as were other risk factors such as duration of diabetes (p much less than 0.001). The tourniquet test is unreliable in predicting the presence or severity of diabetic retinopathy because of its high false negative response rate.

The effect of an aldose reductase inhibitor on cardiovascular performance in patients with diabetes mellitus

Because some aldose reductase inhibitor studies have demonstrated clinical improvement in scored neurological signs and symptoms of diabetic neuropathy, a prospective study of the effect on cardiovascular performance of sorbinil 250 mg/day for 12 months was conducted on patients with diabetic autonomic neuropathy who were free of atherosclerotic coronary artery disease and/or cardiomyopathy. After 1 year of treatment, the study group (n = 14) demonstrated significant improvement in both the resting cardiac output (P = 0.02), and the maximal cardiac output (P = 0.03). This observation suggests that the use of an aldose reductase inhibitor may be useful in treating suboptimal cardiovascular performance in patients with diabetic cardiac autonomic neuropathy.

Autonomic influence on cardiovascular performance in diabetic subjects

PURPOSE

Cardiomyopathy, coronary artery atherosclerosis, or autonomic neuropathy may affect the cardiovascular performance of the diabetic patient. To evaluate the role of parasympathetic nervous system activity on cardiovascular performance, 25 diabetic subjects who lacked symptoms, signs, or objective measurements of ischemia or cardiomyopathy were studied.

PATIENTS AND METHODS

Diabetic subjects were classified according to their RR variation, an index of cardiac parasympathetic nervous system activity. Fourteen diabetic subjects had a normal RR variation of greater than 30 (D-NOR), and 11 diabetic patients had an abnormal RR variation of less than 20 (D-ABN). Fifteen age- and weight-matched, healthy, nondiabetic subjects (NOR) constituted the control group. All subjects had oxygen consumption, multigated acquisition determination of cardiac output, and work product measured before and during supine bicycle maximum exercise testing.

RESULTS

There was no difference in the resting cardiac output among the groups. Resting work product, however, was greatest in the D-ABN group when compared with performance in the other two groups (D-ABN: 11,500 +/- 800; D-NOR: 9,000 +/- 600; NOR: 8,700 +/- 400; p less than 0.0025). This was due to an increase in both heart rate (p less than 0.025) and systolic blood pressure (p less than 0.015). In the diabetic subjects, there was an inverse relationship between the RR variation and resting work product (r = 0.47, n = 25, p less than 0.005). In response to exercise, the percent increase in cardiac output at matched percent maximum oxygen uptake was greatest in the NOR, D-NOR, and D-ABN groups, respectively (analysis of variance, p less than 0.01). In the diabetic subjects, there was a significant relationship between the RR variation and the maximum percent change in cardiac output (r = 0.41, n = 25, p less than 0.02). Compared with the NOR group, the maximum increase in work product was impaired in diabetic subjects (p less than 0.002) and not different between the D-NOR and D-ABN groups.

CONCLUSIONS

The increase in resting work product and the poor cardiac output responses to exercise in the D-ABN group are due to a decrease in cardiac parasympathetic nervous system activity and can be suggested by an abnormal RR variation. This index of parasympathetic nervous system activity can help the physician identify that subset of diabetic patients that may need special consideration when exercise training is prescribed.

Diabetic peripheral neuropathy. Part II. Autonomic neuropathies (continuing education credit)

Diabetic autonomic neuropathies (DAN) are clinical syndromes resulting from impairments of the autonomic nervous system in patients with diabetes mellitus. Since the autonomic nervous system innervates most body organs, any or all of those organs may be affected by DAN. A high index of suspicion is the best diagnostic tool. Proper management, with patient and family education in its center, improves the quality of life of persons with DAN. Undiagnosed and ignored, DAN could cause severe disability and even death.

Diabetic peripheral neuropathy. Part I. Sensorimotor neuropathy (continuing education credit)

Diabetic neuropathy, defined as objective evidence of neural im pairment accompanied by discern ible symptoms, is a common complication of diabetes. Pathologically it is considered a "dying back " neuropathy in which the distal portions of the neurons are first and more severely affected. Both vascular and metabolic hypotheses have been advanced for its patho genesis. Diabetic sensorimotor neuropathy has two subclasses: focal and distal symmetrical polyneuropathy. Signs and symp toms, complications, and guide lines for treatment are listed for the different syndromes. Current research includes investigations of the possible preventive and therapeutic roles of glycemic control and specific therapeutic agents.

Abolition of dopaminergic insulin secretion by beta-adrenergic antagonism

To determine whether the insulinotropic effects of dopamine were mediated through the adrenergic system, dogs were infused with dopamine before or after various combinations of adrenergic and cholinergic blockade. Plasma glucose levels did not change significantly throughout the individual experiments, although cardiovascular effects from both blockade and dopamine infusion were demonstrated. The pronounced in vivo insulinotropic effects of dopamine were abolished by beta-adrenergic blockade with propranolol and all subsequent combinations of propranolol, phentolamine, and atropine. These results contrast with the in vitro suppression of insulin by dopamine, which is abolished by alpha-adrenergic blockade by phentolamine. Therefore, it may be concluded that the prevention of dopamine effects on insulin secretion by adrenergic antagonism is evidence that dopamine exerts its effects on the B cell directly or indirectly through the adrenergic system.

Hypercalcitonemia in pernicious anemia

Gastrin has been suggested as a natural secretogogue of the hormone calcitonin. We have found hypercalcitonemia in 55% of patients with pernicious anemia, and the gastrin levels, although usually increased, did not correlate.

Limited calcitonin reserve in hyperparathyroidism

A comparative study was made of the serum calcitonin levels of patients with hyperparathyroidism. The mean serum calcitonin of those with hyperparathyroidism did not differ significantly from normal persons (mean +/- SEM: 130 +/- 16 pg/ml vs 124 +/- 7 pg/ml, respectively.) Only 0.5% of patients with hyperparathyroidism had values exceeding the upper limits of normal. In contrast, the mean serum calcitonin of patients with hypercalcemia of nonparathyroid etiology was considerably higher than normal (354 +/- 75 pg/ml, p < 0.001)), and 41% exceeded the upper limits of normal. Calcium infusion induced less of an increase in serum calcitonin for patients with hyperparathyroidism than for normal persons. In addition, the diminished responsibility was also present postoperatively. These findings suggest that the prolonged hypercalcemia associated with hyperparathyroidism results in a decreased calcitonin reserve which may persist for unknown reasons. In the clinical evaluation of hypercalcemic patient, the finding of hypercalcitonemia is suggestive evidence against the diagnosis of hyperparathyroidism.

Low T4 and low FT4I in seriously ill patients: concise communication

Of 128 euthyroid hospitalized patients with nonthyroidal illnesses (NTI), 33% had a low total thyroxine (T4). Forty-three percent of the latter patients had a low free thyroxine index. In euthyroid patients with NTI, free T4 was, with rare exceptions, within the range for well euthyroid controls. The free T4, as determined by two different radioimmunoassays, was diagnostically low in 34 of 37 hypothyroid patients without NTI. However, in hypothyroid patients with NTI, the free T4 determination was less informative. Only four of ten patients had a low free T4 by the Corning test, and none of ten were low by the Clinical Assays test. Our data suggest that patients with NTI frequently have low T4 and low FT4I, despite being euthyroid. Low free T4 strongly suggests hypothyroidism, but normal free T4 in patients with NTI does not exclude hypothyroidism.

Calcitonin in thyroidectomized patients

Hypothyroid patients with total or near-total thyroidectomy were found to have detectable immunoreactive calcitonin in the serum and urine. These findings suggest that human calcitonin may be secreted by extrathyroidal tissues.