Selective inhibition of phosphodiesterase 7 enzymes reduces motivation for nicotine use through modulation of mesolimbic dopaminergic transmission.

Background: About 5 million people die from diseases related to nicotine addiction and tobacco use each year. Nicotine-induced increase of corticomesolimbic dopaminergic (DAergic) transmission and hypodopaminergic conditions occurring during abstinence are important for maintaining drug-use habits. Methods: We examined the notion of re-equilibrating DAergic transmission by inhibiting phosphodiesterase 7 (PDE7), an intracellular enzyme highly expressed in the corticomesolimbic circuitry and responsible for the degradation of cyclic adenosine monophosphate (cAMP), the main second messenger modulated by DA receptor activation. Results: Using selective PDE7 inhibitors, we demonstrated in male rats that systemic PDE7 enzyme inhibition reduced nicotine self-administration and prevented reinstatement to nicotine seeking evoked by cues or by the pharmacological stressor yohimbine. The effect was also observed by direct application of the PDE7 inhibitors into the nucleus accumbens (NAc) shell but not into the core. Inhibition of PDE7 resulted in increased DA- and cAMP-regulated neuronal phosphoprotein (DARPP-32) and cAMP response element-binding protein (CREB) and their phosphorylated forms in the NAc. It also enhanced the DA D1 receptor agonism-mediated effects, indicating potentiation of protein kinase A (PKA)-dependent transmission downstream of D1 receptor activation. In electrophysiological recordings from DA neurons in the lateral posterior ventral tegmental area (VTA), the PDE7 inhibitors attenuated the spontaneous activity of DA neurons. This effect was exerted through the potentiation of D1 receptor signaling and the subsequent facilitation of γ-aminobutyric acid (GABA) transmission. The PDE7 inhibitors did not elicit conditioned place preference and did not induce intravenous self-administration, indicating lack of reinforcing properties. Conclusions: PDE7 inhibitors have the potential to treat nicotine abuse.SIGNIFICANCE STATEMENTThe World Health Organization (WHO) estimates that there are 1.25 billion smokers worldwide, representing one third of the global population over the age of 15. Nicotine-induced increase of corticomesolimbic dopaminergic (DAergic) transmission and hypodopaminergic conditions occurring during abstinence are critical for maintaining drug-use habits. Here we demonstrate that nicotine consumption and relapse to nicotine seeking are attenuated by re-equilibrating DAergic transmission through inhibition of phosphodiesterase 7 (PDE7), an intracellular enzyme responsible for the degradation of cyclic adenosine monophosphate (cAMP), the main second messenger modulated by DA receptor activation. PDE7 inhibition may represent a novel treatment approach to aid smoking cessation.

Secondary Complement Deficiency Impairs Anti-Microbial Immunity to Klebsiella pneumoniae and Staphylococcus aureus During Severe Acute COVID-19.

A high incidence of secondary Klebsiella pneumoniae and Staphylococcus aureus infection were observed in patients with severe COVID-19. The cause of this predisposition to infection is unclear. Our data demonstrate consumption of complement in acute COVID-19 patients reflected by low levels of C3, C4, and loss of haemolytic activity. Given that the elimination of Gram-negative bacteria depends in part on complement-mediated lysis, we hypothesised that secondary hypocomplementaemia is rendering the antibody-dependent classical pathway activation inactive and compromises serum bactericidal activity (SBA). 217 patients with severe COVID-19 were studied. 142 patients suffered secondary bacterial infections. Klebsiella species were the most common Gram-negative organism, found in 58 patients, while S. aureus was the dominant Gram-positive organism found in 22 patients. Hypocomplementaemia was observed in patients with acute severe COVID-19 but not in convalescent survivors three months after discharge. Sera from patients with acute COVID-19 were unable to opsonise either K. pneumoniae or S. aureus and had impaired complement-mediated killing of Klebsiella. We conclude that hyperactivation of complement during acute COVID-19 leads to secondary hypocomplementaemia and predisposes to opportunistic infections.

Novel drug OMS103HP reduces pain and improves joint motion and function for 90 days after arthroscopic meniscectomy.

PURPOSE: This phase 2 study compared OMS103HP (Omeros, Seattle, WA) with control (lactated Ringer's) irrigation solution in patients undergoing arthroscopic partial meniscectomy. METHODS: This was a prospective, multicenter, double-blind, randomized, vehicle-controlled, parallel-group study. Safety and postoperative pain, range of motion, and self-reported function were evaluated for 90 days. Statistical results were based on univariate analysis of variance and repeated-measures analyses. RESULTS: Mean visual analog scale (VAS) pain scores within 24 hours after discharge from the recovery room showed more pain in the control group beginning at 2 hours and peaking at 8 hours. Univariate analysis of variance of mean VAS scores over the 24-hour period did not meet statistical significance. Repeated-measures analysis yielded a statistically significant difference (P = .004) for time-by-treatment interaction, showing a clear drug benefit over time based on VAS scores. There were statistically significant differences at day 7 between the groups in passive flexion without pain (P = .022). The proportion of patients achieving flexion of 95° or greater, 110°, and 125° was greater for the OMS103HP group. The Knee Injury and Osteoarthritis Outcome Score (KOOS) showed statistically significant differences (P ≤ .05) between the OMS103HP and control groups for 4 of 5 outcomes (symptoms, pain, sport and recreation, and knee-based quality of life but not activities of daily living). All scores showed a treatment effect through day 90. The overall incidence of adverse events and abnormal laboratory values for the OMS103HP and control groups was similar. Serious adverse events occurred in 1 control patient. CONCLUSIONS: In this study of patients with meniscal tears who underwent simple debridement, the use of OMS103HP resulted in reduced acute postoperative pain (measured by VAS over the first 24 hours postoperatively), reduced pain during recovery (measured by the KOOS pain subscale, which measures both background levels of pain and exacerbations caused by movements or activities), improved postoperative knee motion, and improved functional outcomes as assessed with the KOOS Knee Survey. Clinical benefits of OMS103HP were consistent and sustained throughout 90 days of postoperative follow-up. LEVEL OF EVIDENCE: Level I, prospective, randomized, controlled trial.

Novel drug product to improve joint motion and function and reduce pain after arthroscopic anterior cruciate ligament reconstruction.

PURPOSE: OMS103HP, an investigational drug product containing ketoprofen, amitriptyline, and oxymetazoline, is added to arthroscopic irrigation solution. OMS103HP was evaluated in patients undergoing arthroscopic anterior cruciate ligament reconstruction to assess the drug's safety and ability to improve postoperative knee function and motion, reduce postoperative pain, and allow earlier return to work. METHODS: This was a prospective, double-blind, vehicle-controlled, parallel-group, randomized study. Allograft anterior cruciate ligament reconstruction patients in both treatment and vehicle control groups were monitored for safety and efficacy (e.g., measurements of knee function and motion, pain, and return to work) over a 30-day postoperative period. The efficacy endpoints of primary interest were assessed by use of both responder and time-to-event analyses. RESULTS: There were statistically significant differences (P < or = .05) between the OMS103HP and vehicle control groups in the endpoints of knee function (knee function composite and straight-leg raise component of knee function composite), range of motion (median number of days to maximum passive flexion of 90 degrees or greater without pain and time to discontinuation of continuous passive motion), quadriceps and hamstring muscle strength, successful pain management, and return to work. The overall incidences of adverse events and abnormal clinical laboratory values for both OMS103HP- and vehicle-treated subjects were similar, and none was attributed to OMS103HP. CONCLUSIONS: The clinical benefits of OMS103HP in this study were reduced postoperative pain; improved postoperative knee motion, quadriceps and hamstring muscle strength, and knee function; and earlier return to work as measured by surgeons, nurses, and physical therapists across repeated clinic visits and rehabilitation sessions and recorded by patients in daily diaries. The drug was well tolerated.

The effect of intravesical ketoprofen on acetylcholine-evoked urinary bladder contractility and detrusor overactivity in the anesthetized rabbit model.

Intraurethral procedures such as the transurethral resection of the prostate can generate detrusor overactivity and bladder irritability. The rabbit model of detrusor overactivity has proven to be an excellent model to study the effects of drugs on detrusor overactivity. Using this model, we evaluated the responses to intravesical ketoprofen. In this model, each rabbit is anesthetized and the right external carotid artery is cannulated for blood pressure monitoring. A catheter is inserted through the femoral artery and is used for administration of acetylcholine (Ach). The bladder is exposed and catheterized for bladder pressure monitoring and drug addition and the proximal urethra is ligated. Cystometry is performed, the bladder drained, and 20 ml buffer placed in the bladder. After 30 min Ach is injected proximal to the vesical artery and the response of the bladder and blood pressure is recorded. Ach administration is repeated at 10-min intervals until three consistent responses are obtained. The bladder is drained and 20 ml of ketoprofen (100 microM final concentration) is placed in the bladder. Ach injections are repeated as given above at 10 min intervals and observed for 4 h. At the end of the experiment, a second cystometry is performed. The following is a summary of the results: Ketoprofen had no effect on either micturition pressure or the intravesical volume at micturition. Ketoprofen administration resulted in a progressive 50% decrease in the response to Ach. Ketoprofen mediated a progressive decrease in detrusor overactivity amplitude and frequency, reaching a maximum at 120-180 min.

Intracameral phenylephrine and ketorolac injection (OMS302) for maintenance of intraoperative pupil diameter and reduction of postoperative pain in intraocular lens replacement with phacoemulsification.

BACKGROUND: The purpose of this study was to evaluate the effect of OMS302 on intraoperative pupil diameter and early postoperative ocular pain when administered during intraocular lens replacement surgery. METHODS: Four hundred and six patients (406 study eyes; 202 in the OMS302 group and 204 in the placebo group) were entered into this randomized, double-masked, placebo-controlled, multicenter Phase III study, which was conducted at 15 centers in the USA and the Netherlands. The patients received OMS302 (60.75 mM phenylephrine HCl and 11.25 mM ketorolac tromethamine) or placebo in irrigation solution during intraocular lens replacement. No other changes in procedure were required. Coprimary endpoints were change in pupil diameter over time from surgical baseline to end of procedure and patient-reported ocular pain during the first 12 hours postoperatively. Secondary endpoints included additional measures of pupil diameter and postoperative pain. RESULTS: OMS302 was superior to placebo in maintaining intraoperative mydriasis, preventing miosis, and reducing postoperative pain. The weighted mean (standard error) difference (OMS302 - placebo) in change in the area under the curve from baseline for pupil diameter was 0.590 ([0.049]; 95% confidence interval 0.494 to 0.686; P<0.0001). For ocular pain scores, the weighted mean (standard error) difference was -4.580 ([1.192]; 95% confidence interval -6.917 to 2.244; P=0.0002). All secondary efficacy results favored OMS302. Specifically, analyses supporting prevention of miosis (patients with ≥6 mm pupil diameter at completion of cortical clean-up and those with <6 mm diameter at any time during surgery) were significant for OMS302 (95.9% versus 77.0% and 9.2% versus 38.0%, respectively; P<0.0001 for each endpoint). OMS302 was well tolerated and not associated with any unexpected adverse events. CONCLUSION: OMS302 maintained mydriasis, prevented miosis, and reduced early postoperative pain when administered in irrigation solution during intraocular lens replacement, with a safety profile similar to that of placebo. OMS302 is preservative-free and bisulfite-free, and its administration does not require any modification to the surgical procedure.