Solving the crisis in psychopharmacological research: Cellular-membrane(s) pharmacology to the rescue?

An evolutionary analysis of the applicability and utility of the clinico-pathological method in psychiatry

Unlike other medical specialties, psychiatry has not been involved in the theoretical shift that replaced the syndromal approach with the clinico-pathological method, which consists in explaining clinical manifestations by reference to morbid anatomical and physiological changes. Past and present discussions on the applicability of the clinico-pathological method in psychiatry are based on a pre-Darwinian concept of biology as the study of proximate causation. Distinguishing between mediating mechanisms and evolved functions, an evolutionary perspective offers an original contribution to the debate by overcoming the opposite views of dualism (i.e., the clinico-pathological method is not applicable to disorders of the mind) and neuroessentialism (i.e., the definitive way of explaining psychiatric disorders is by reference to the brain and its activity). An evolutionary perspective offers original insights on the utility of the clinico-pathological method to solve critical questions of psychiatric research and clinical practice, including the distinction between mental health and illness, a better understanding of the etiology and pathophysiology, the classification and differential diagnosis of psychiatric disorders, and the development of more efficacious psychiatric treatments.

Fluidized or not fluidized? Biophysical characterization of biohybrid lipid/protein/polymer liposomes and their interaction with tetracaine

BACKGROUND

Nanomedicine and the pharmaceutical industry demand the investigation of new biomaterials to improve drug therapies. Combinations of lipids, proteins, and polymers represent innovative platforms for drug delivery. However, little is known about the interactions between such compounds and this knowledge is key to prepare successful drug delivery systems.

METHODS

Biophysical properties of biohybrid vesicles (BhVs) composed of phospholipids, proteins, and amphiphilic block copolymers, assembled without using organic solvents, were investigated by differential scanning calorimetry and dynamic light scattering. We studied four biohybrid systems; two of them included the effect of incorporating tetracaine. Thermal changes of phospholipids and proteins when interacting with the amphiphilic block copolymers and tetracaine were analyzed.

RESULTS

Lysozyme and the copolymers adsorb onto the lipid bilayer modifying the phase transition temperature, enthalpy change, and cooperativity. Dynamic light scattering investigations revealed relevant changes in the size and zeta potential of the BhVs. Interestingly, tetracaine, a membrane-active drug, can fluidize or rigidize BhVs.

CONCLUSIONS

We conclude that positively charged regions of lysozyme are necessary to incorporate the block copolymer chains into the lipid membrane, turning the bilayer into a more rigid system. Electrostatic properties and the hydrophilic-lipophilic balance are determinant for the stability of biohybrid membranes.

GENERAL SIGNIFICANCE

This investigation provides fundamental information associated with the performance of biohybrid drug delivery systems and can be of practical significance for designing more efficient drug nanocarriers.

Drug Development for New Psychiatric Drug Therapies

Drug development is an expensive, high risk, and highly regulated process. Only about 6.2% of new molecules tested for mental disorders eventually achieve Food and Drug Administration (FDA) approval. New molecular entities are produced, and extensive in vitro animal testing is performed before they are evaluated in humans. The compound is used in animals to predict clinical effects in humans, and studies addressing pharmacodynamics, pharmacokinetics, toxicology, and mutagenicity are conducted. Human research proceeds in three stages with the ultimate goal of proving that a new agent is efficacious and safe for a treatment of a specific disease in humans. If efficacy and safety are demonstrated in two Phase III studies, then the sponsor can submit a new drug application (NDA) to the FDA. The FDA oversees each step of the process to assure that good research practices are followed, data integrity is assured, and human research subjects are protected.

Withdrawal effects confounding in clinical trials: another sign of a needed paradigm shift in psychopharmacology research

Randomized controlled trials' ability to produce evidence useful for people to decide whether to take, continue taking, or stop taking psychotropic drugs has been intensely critiqued, along with the trials' commercial, ideological, and regulatory contexts. This article applies the critique to the topic of withdrawal effects confounding the outcomes of relapse-prevention trials where prescribed psychotropic drugs are discontinued. Until recently, the complexity and reach of withdrawal and post-withdrawal effects were neglected by mainstream psychiatry, but not by lay users of prescribed psychotropics. This article discusses withdrawal effects as part of the pharmacology of psychotropic drugs but shaped by psychosocial factors, and possibly shaping the presentation of psychological distress generally. It outlines biases and misconceptions in assumptions, design, and reporting of general efficacy trials and findings from a recent review of 80 discontinuation trials. In theory, relapse-prevention trials are tautological and exaggerate efficacy. In publications, they pay little attention to the central feature of their design, favor abrupt or rapid discontinuations, do not attend to environmental factors, and provide insufficient data to allow re-analyses. Thus, relapse-prevention RCTs likely confound the detection of their main outcome of interest: "relapse." Using slower tapers, active placebo controls, and specific covariates in analyses would reduce the risk of withdrawal confounding, and better reporting would reduce the opaqueness of trials. The crisis in psychopharmacology is fueled partly by the disconnect between claims of therapeutic efficacy from so-called best-evidence methods despite unchanging population-level indicators of psychiatric sickness. Only by "stacking the deck" against trial sponsors' hoped-for outcomes can psychopharmacology trials regain scientific credibility.