INTERCHANGEABILITY OF VIRAL VACCINES FOR IMMUNIZATION

The review presents the results of the analysis of domestic and foreign scientific literature on the interchangeability of hepatitis A, B and influenza vaccines. The WHO materials, regulatory documents, data from scientific literature of foreign countries and Russia about the vaccine interchangeability are summarized. The problem of objective assessment of interchangeability of drugs is relevant worldwide. The definition of an "interchangeable drug" does not draw a clear line between the interoperability criteria for chemical and immunobiological drugs. The official guidance documents on immunization adopted in several countries define "interchangeability" as the practice of transition from a vaccine available from a certain manufacturer to a similar vaccine available from another manufacturer. The term "interchangeable" can be applied to immunobiological drugs if one of the drugs can be replaced with the other in the course of vaccination. The concept of interchangeability applies to vaccines that do not differ in efficacy (immunological, preventive, epidemiological) and safety and are used in an immunization course involving multiple administration of these vaccines. The definition of interchangeability is important in order to address the problem of replacing unidirectional vaccines available from different manufacturers when purchasing vaccines included in the national schedule of preventive vaccinations and in the schedule of preventive vaccination on epidemic indications. One of the most important conditions for "interchangeability" of vaccines is their application in accordance with the recommended schedule of administration and the dosage indicated by the manufacturer. Research data show that vaccines can be interchangeable if used in accordance with the recommended schedule of administration and the dosage specified by the manufacturer. Control agencies of many countries issue recommendations regulating the procedure of vaccine replacement in case of necessity. However, there are no special regulations of vaccine interchangeability in Russia. The concept of vaccine "interchangeability" should be extended to the continuation of a course of vaccinations in a particular person with a vaccine of another manufacturer and the possibility of applying similar vaccines available from different manufacturers.

Antiparkinsonian effect of nerve growth factor adsorbed on polybutylcyanoacrylate nanoparticles coated with polysorbate-80

The study examined the antiparkinsonian effect of nerve growth factor adsorbed on the surface of polybutylcyanoacrylate nanoparticles coated with polysorbate-80 surfactant. The parkinsonian syndrome in C57B1/6 mice was provoked by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. The basic symptoms of the parkinsonian syndrome decreased under the action of the nerve growth factor adsorbed on nanoparticles coated with polysorbate-80, which was seen from decreased rigidity and increased locomotor activity compared to control mice receiving with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine alone. This effect of nerve growth factor on nanoparticles persisted after 7 and 21 days after single injection of the neurotoxin. These data attest to the possibility of using nanoparticles prepared from amphiphilic polymers and coated with polysorbate-80 for the delivery of nerve growth factor into the brain during systemic treatment.

The porphyrin-fullerene nanoparticles to promote the ATP overproduction in myocardium: 25Mg2+-magnetic isotope effect

This is a first case ever reported on the fullerene-based low toxic nanocationite particles (porphyrin adducts of cyclohexyl fullerene-C(60)) designed for targeted delivery of the paramagnetic magnesium stable isotope to the heart muscle providing a sharp clinical effect close to about 80% recovery of the tissue hypoxia symptoms in less than 24 h after a single injection (0.03-0.1 LD(50)). A whole principle of this therapy is novel: (25)Mg(2+)-magnetic isotope effect selectively stimulates the ATP overproduction in the oxygen-depleted cells due to (25)Mg(2+) released by the nanoparticles. Being membranotropic cationites, these "smart nanoparticles" release the overactivating paramagnetic cations only in response to the metabolic acidic shift. The resulting positive changes in the heart cell energy metabolism may help to prevent and/or treat the local myocardial hypoxic disorders and, hence, protect the heart muscle from a serious damage in a vast variety of the hypoxia-caused clinical situations including both doxorubicin and 1-methylnicotineamide cardiotoxic side effects. Both pharmacokinetics and pharmacodynamics of the drug proposed make it suitable for safe and efficient administration in either single or multi-injection (acute or chronic) therapeutic schemes.

Effects of apolipoproteins on dalargin transport across the blood-brain barrier

Antinociceptive activity of dalargin (7.5 mg/kg) adsorbed on poly(butyl)cyanoacrylate nanoparticles with different coating was studied on outbred albino mice by the tail-flick test. poly(butyl)cyanoacrylate nanoparticles without coating did not increase the antinociceptive activity of dalargin and hence, did not increase its transport across the blood-brain barrier. poly(butyl)cyanoacrylate nanoparticles coated with apolipoprotein B, apolipoprotein E, and polysorbate 80 increased the transport of dalargin across the blood-brain barrier. Delivery of dalargin to the brain was most effective in case of using poly(butyl)cyanoacrylate nanoparticles with polysorbate 80 coating and subsequent supercoating with apolipoprotein E.

Covalent Linkage of Apolipoprotein E to Albumin Nanoparticles Strongly Enhances Drug Transport into the Brain

Drug delivery to the brain is becoming more and more important but is severely restricted by the blood-brain barrier. Nanoparticles coated with polysorbates have previously been shown to enable the transport of several drugs across the blood-brain barrier, which under normal circumstances is impermeable to these compounds. Apolipoprotein E was suggested to mediate this drug transport across the blood-brain barrier. In the present study, apolipoprotein E was coupled by chemical methods to nanoparticles made of human serum albumin (HSA-NP). Loperamide, which does not cross the blood-brain barrier but exerts antinociceptive effects after direct injection into the brain, was used as model drug. Apolipoprotein E was chemically bound via linkers to loperamide-loaded HSA-NP. This preparation induced antinociceptive effects in the tail-flick test in ICR mice after i.v. injection. In contrast, nanoparticles linked to apolipoprotein E variants that do not recognize lipoprotein receptors failed to induce these effects. These results indicate that apolipoprotein E attached to the surface of nanoparticles facilitates transport of drugs across the blood-brain barrier, probably after interaction with lipoprotein receptors on the brain capillary endothelial cell membranes.

Amino Acid Composition of Nephrophyt, a New Complex Plant Preparation and Its Possible Role in Correction of Mercuric Chloride-Induced Acute Renal Failure in Rats

Amino acid composition of a new Russian nephroprotective drug Nephrophyt (a complex mixture of dry plant extracts) was studied for the first time in order to validate its pharmacological effects in rats with mercuric chloride-induced nephropathy. The concentration of pyrrolidone amino acids and serine in this preparation was extremely high, which is uncommon for plant raw material. These data are in good correlation with pronounced nephroprotective effect and agree with published reports on pharmacological effects of individual amino acids and their metabolites. The prospects of the use of this preparation based on the data on its amino acid composition are discussed.

Significant entry of tubocurarine into the brain of rats by adsorption to polysorbate 80-coated polybutylcyanoacrylate nanoparticles: an in situ brain perfusion study

The possibility of using polysorbate 80-coated polybutylcyanoacrylate nanoparticles to deliver low molecular polar hydrophilic drugs to the CNS has been studied. Tubocurarine (a quaternary ammonium salt) does not penetrate the normal intact blood-brain barrier. However, the injection of this drug directly into the cerebral ventricles of the brain provokes the development of epileptiform seizures as assessed by electroencephalogram (EEG). An in situ perfused rat brain technique was used as an experimental technique together with a simultaneous recording of the EEG. Nanoparticles were prepared by butylcyanoacrylate polymerization in an acidic medium. Fifteen minutes after the introduction of tubocurarine-loaded polysorbate 80-coated nanoparticles into the perfusate, epileptiform spikes in the EEG appeared. Intraventricular injection of tubocurarine caused the appearance of the EEG seizures 5 min after administration. Neither tubocurarine solution nor tubocurarine-loaded nanoparticles without polysorbate 80 or a mixture of polysorbate 80 and tubocurarine were able to influence the EEG. Thus only the loading of tubocurarine onto the polysorbate 80-coated nanoparticles appears to enable the transport of this quaternary ammonium compound through the blood-brain barrier.

Delivery of loperamide across the blood-brain barrier with polysorbate 80-coated polybutylcyanoacrylate nanoparticles

PURPOSE

The possibility of using polysorbate 80-coated nanoparticles for the delivery of the water insoluble opioid agonist loperamide across the blood-brain barrier was investigated. The analgesic effect after i.v. injection of the preparations was used to indicate drug transport through this barrier.

METHODS

Loperamide was incorporated into PBCA nanoparticles. Drug-containing nanoparticles were coated with polysorbate 80 and injected intravenously into mice. Analgesia was then measured by the tail-flick test.

RESULTS

Intravenous injection of the particulate formulation resulted in a long and significant analgesic effect. A polysorbate 80 loperamide solution induced a much less pronounced and very short analgesia. Uncoated nanoparticles loaded with loperamide were unable to produce analgesia.

CONCLUSIONS

Polysorbate 80-coated PBCA nanoparticles loaded with loperamide enabled the transport of loperamide to the brain.

Passage of peptides through the blood-brain barrier with colloidal polymer particles (nanoparticles)

Transport of the hexapeptide dalargin across the blood-brain barrier was accomplished using a nanoparticle formulation. The formulation consisted of dalargin bound to poly(butyl cyanoacrylate) nanoparticles by sorption, coated with polysorbate 80. Intravenous injection of this formulation to mice resulted in an analgesic effect. All controls, including a simple mixture of the three components (drugs, nanoparticles, and surfactant) mixed directly before i.v. injection, exhibited no effect. Analgesia was also prevented by pretreatment with naloxone. Fluorescent and electron microscopic studies indicated that the passage of the particle-bound drug occurred by phagocytic uptake of the polysorbate 80-coated nanoparticles by the brain blood vessel endothelial cells.

Employment of magnet-susceptible microparticles for the targeting of drugs

It has been demonstrated in cats that magnet-susceptible microspheres and liposomes containing neuromuscular blocking agents (dipyronium, pyrocurinum and diadonium) caused a deeper inhibition of the neuromuscular transmission in the limb placed in the magnetic field than in the control limb located beyond the field. The microparticles containing a short-acting neuromuscular blocking agent diadonium appeared to have the highest selectivity of action. The present method allows a pronounced neuromuscular block in a target area to be achieved without noticeable effect on PCO2 of the exhaled air.