A small percentage of patients, some of whom have taken many HIV drugs in the past, have multidrug-resistant HIV, limiting their treatment options
HIV naturally mutates and eventually develops resistance to ARVs, which are then rendered ineffective. Patients infected with drug resistant strains of HIV are therefore commonly moved to alternative regimens known as 2nd
HIV resistance to the potent antiretroviral drug tenofovir (Viread) has become increasingly common.
A new medication, Trogarzo (ibalizumab-uiyk), has however been approved by the US Food and Drug Administration to treat Aids-causing HIV that has not responded to other antiretroviral medications.
A new class of medications
Trogarzo is given intravenously once every 14 days in combination with other antiretroviral drugs, the Food and Drug Administration (FDA) said in a news release.
"While most patients living with HIV
can be successfully treated using a combination of two or more antiretroviral drugs, a small percentage of patients who have taken many HIV drugs
in the past have multidrug resistant HIV, limiting their treatment options," said Dr Jeff Murray, deputy director of the agency's Division of Antiviral Products.
"Trogarzo is the first drug in a new class of antiretroviral medications that can provide significant benefit to patients who have run out of HIV treatment options," Dr Murray added.
Trogarzo was evaluated in clinical studies involving 40 people who continued to have high levels of HIV, despite use of antiretroviral drugs. After 24 weeks of Trogarzo and other drugs, 43% of trial participants achieved HIV suppression, the FDA said.
The most common adverse reactions to Trogarzo were diarrhoea, dizziness, nausea and rash. More severe side effects included immune system abnormalities.
More On Trogazo
Discovered and developed by TaiMed Biologics, Trogarzo™
is used in combination with other antiretroviral medicines.
TaiMed Biologics submitted the new drug application (NDA) for Trogarzo™
to the US Food and Drug Administration (FDA) in May 2017. Initially granted fast-track, priority review and breakthrough therapy designations, the drug was approved in March 2018 and has been granted orphan drug designation.
HIV-1 infection causes and symptoms
is among the two types of HIV virus that cause acquired immune deficiency syndrome (AIDS). HIV-1 is more virulent and infective compared with HIV-2.
HIV infects and destroys the immune system’s white blood cells, which are also known as CD4+ cells. Patients living with HIV-1 infection typically experience symptoms such as recurring fever, skin rash, chronic fatigue
, persistent diarrhoea, arthralgia and myalgias. Some patients may experience relatively minimal symptoms.
The Joint United Nations Programme on HIV/AIDS (UNAIDS) estimates that more than 20.9 million people were living with HIV in June 2017.
Trogarzo’s mechanism of action
contains Ibalizumab-uiyk, which is a recombinant humanised monoclonal antibody of immunoglobulin G (IgG) isotype 4.
The drug blocks the HIV-1 virus from infecting CD4+ T-cells, which are the primary receptors for HIV. It binds to the second extracellular domain of the CD4+ T receptor and prevents the viral transmissions that occur through cell-to-cell fusion and preserve normal immunological function.
Clinical trials on Trogarzo™
The FDA’s approval
(ibalizumab) was based on results obtained from a Phase III clinical trial named TMB-301.
“Trogarzo™ contains Ibalizumab-uiyk, which is a recombinant humanised monoclonal antibody of immunoglobulin G (IgG) isotype 4.”
This single-arm, multi-centre clinical trial focused on a small patient population with limited treatment options.
It enrolled 40 treatment-experienced patients with multidrug-resistant HIV-1 (MDR-HIV-1), who were previously treated with more than ten anti-retroviral drugs. The patients were administered with 2,000mg Trogarzo™
intravenously once every 14 days in combination with other antiretroviral medications.
Results from the study showed a significant reduction in the viral load within seven days of the first dose. Trogarzo™
also maintained the treatment response rate when combined with at least one other active ART for up to 24 weeks of treatment.
The primary endpoint of the study was achieved in more than 80% of participants with 70% viral load reduction from baseline within seven days of administering 2,000mg Trogarzo™
. Following 24 weeks of Trogarzo™
use in combination with other anti-retroviral drugs, 43% of patients achieved HIV-RNA suppression.
The most common side effects reported in patients treated with Trogarzo™
included diarrhoea, dizziness, nausea, rash and severe changes in the immune system, which is referred to as Immune Reconstitution Inflammatory Syndrome.
was also studied in a randomised, double-blinded, multi-centre Phase 2b trial (TMB-202), which enrolled 113 participants. The trial studied two different intravenous doses given at two different dosing intervals, one dose for every four weeks and the other for every two weeks.
Both the studies tested subjects for the presence of anti-ibalizumab antibodies. Trogarzo™
has been administered to a total of 292 patients in clinical trials.
Marketing commentary on TaiMed Biologics
Founded in 2007, TaiMed is a Taiwan-based biotechnology company developing products for unmet medical needs. The company’s main focus is in the area of oncology and HIV.
is TaiMed’s first approved therapy for HIV. The company signed a distribution agreement with Theratechnologies in March 2016 to market the drug in the US and Canada.
In March 2017, the distribution agreement was amended to grant Theratechnologies with commercialisation rights for Trogarzo™
in the European territory including the EU, Israel, Norway, Russia and Switzerland.
Reference: USFDA & Staff Writer/TMN