Immunostimulatory effects on THP-1 cells by peptide or protein pharmaceuticals associated with injection site reactions

New Therapies and Strategies to Curb HIV Infections with a Focus on Macrophages and Reservoirs

More than 80 million people worldwide have been infected with the human immunodeficiency virus (HIV). There are now approximately 39 million individuals living with HIV/acquired immunodeficiency syndrome (AIDS). Although treatments against HIV infection are available, AIDS remains a serious disease. Combination antiretroviral therapy (cART), also known as highly active antiretroviral therapy (HAART), consists of treatment with a combination of several antiretroviral drugs that block multiple stages in the virus replication cycle. However, the increasing usage of cART is inevitably associated with the emergence of HIV drug resistance. In addition, the development of persistent cellular reservoirs of latent HIV is a critical obstacle to viral eradication since viral rebound takes place once anti-retroviral therapy (ART) is interrupted. Thus, several efforts are being applied to new generations of drugs, vaccines and new types of cART. In this review, we summarize the antiviral therapies used for the treatment of HIV/AIDS, both as individual agents and as combination therapies, and highlight the role of both macrophages and HIV cellular reservoirs and the most recent clinical studies related to this disease.

Development of a HPLC fluorometric method for the quantification of enfuvirtide following in vitro releasing studies on thermosensitive in situ forming gel

Due to the presence of peptidase and protease in the gastrointestinal tract, peptides are subjected to digestion and inactivation when administrated orally. To avoid degradation and maintain the desired efficacy of peptide drugs, there is a demand to develop transdermal and intradermal delivery systems. This requires efficient and specific analytical methods to separate and quantify the peptide drugs from the formulation and the skin matrix in the early stages of pharmaceutical development. A high-performance liquid chromatography (HPLC) system equipped with a fluorometric detector was used to quantify enfuvirtide, which is the first fusion inhibitor for HIV treatment. The HPLC method was developed and validated according to the ICH Q2(R1) guidelines. The viability of the method was demonstrated during in vitro studies, where samples were analysed following intradermal administration of a thermosensitive in situ forming gel. Compared with previously reported methods, this assay proved efficient, sensitive and accurate, with a detection limit of 0.74 μg/mL and a run time of 9 min, mitigating the use of any internal standards and detergents. The addition of an organic solvent to the samples successfully solved the problem of low recovery caused by the adsorption of the drug to the plastic consumables in the sample treatment process. The amount of enfuvirtide releasing from the in situ gel through skin after 7 hours was 16.25 ± 7.08 μg, which was significantly lower than the reconstituted FUZEON^® itself (26.68 ± 10.45 μg), showing a longer release profile. The results may be beneficial as a constructive input for future enfuvirtide quantification within a preclinical setting through in vitro release studies across the skin.

Comparability study of monocyte derived dendritic cells, primary monocytes, and THP1 cells for innate immune responses

Immunogenicity is one major challenge to the successful development of biotherapeutics because it could adversely affect PK/PD, safety, and efficacy. Preclinical immunogenicity risk assessment strategies and assays have been developed and implemented to screen and optimize discovery molecules. Internalization by antigen presenting cells (APC) and innate immune activation are initial prerequisite steps in eliciting immune responses to biotherapeutics. Dendritic cells (DC)- and monocyte-based assays are employed to interrogate such risks, and their value has been well documented in the literature. However, these assays have limited throughput, exhibit higher variability, and entail lengthy and complex procedures as they are based on primary cells such as peripheral blood mononuclear cells (PBMC) from individual donors. Herein, we investigated THP1 cells as surrogate cells to study APC internalization and innate immune activation. Comparability studies showed that THP1 cells could resemble innate immune responses of monocyte-derived DC and primary CD14+ monocytes using a panel of therapeutic antibodies. In addition, an automated high throughput THP1 internalization assay was qualified to enable risk assessment at pre‑lead stages. The results demonstrated that THP1 cells can be utilized to assess immunogenicity risk in a high throughput manner.