Clinical Trial

Disease: Induced Long-term Immunity in COVID-19 Patients, (NCT04990557)

Disease info:

COVID-19 is the infectious disease caused by the coronavirus, SARS-CoV-2, which is a respiratory pathogen.

The most common symptoms of COVID-19 are: fever, dry cough, fatigue

Other symptoms that are less common and may affect some patients include: loss of taste or smell, nasal congestion, conjunctivitis (also known as red eyes), sore throat, headache, muscle or joint pain, different types of skin rash, nausea or vomiting, diarrhea, chills or dizziness.

Most people (about 80%) recover from the disease without needing hospital treatment. About 20% of those who get COVID-19 become seriously ill and require oxygen, with 5% becoming critically ill and needing intensive care.

Complications leading to death may include respiratory failure, acute respiratory distress syndrome (ARDS), sepsis and septic shock, thromboembolism, and/or multiorgan failure, including injury of the heart, liver or kidneys.

In rare situations, children can develop a severe inflammatory syndrome a few weeks after infection.

In most situations, a molecular test is used to detect SARS-CoV-2 and confirm COVID-19. Polymerase chain reaction (PCR) is the most commonly used molecular test. Samples are collected from the nose and/or throat with a swab. Molecular tests detect virus in the sample by amplifying viral genetic material to detectable levels. For this reason, a molecular test is used to confirm an active infection, usually within a few days of exposure and around the time that symptoms may begin. 

Rapid tests (sometimes known as a rapid diagnostic test – RDT) detect viral proteins (known as antigens). Samples are collected from the nose and/or throat with a swab. These tests are cheaper than PCR and will offer results more quickly, although they are generally less accurate. 

Official title:
CRISPR/Cas9-modified Human T Cell ( PD-1and ACE2 Knockout Engineered T Cells ) for Inducing Long-term Immunity in COVID-19 Patients


Name: Mahmoud R Elkazzaz, M.Sc of Biochemistry

Phone: +201090302015



Mahmoud Ramadan mohamed Elkazzaz


Not yet disclosed. 

Study start:
Aug. 1, 2021
16 participants
Gene editing method:
Type of edit:
Gene knock-out
Programmed cell death protein 1 (PD-1), Angiotensin-converting enzyme 2 (ACE2)
Delivery method:
- Ex-vivo
IND Enabling Pre-clinical
Phase I Safety
Phase II Safety and Dosing
Phase III Safety and Efficacy

Status: Unknown


This study will assess the safety of PD-1 knockout engineered T cells as genetically modified memory T cells capable of providing long-term immunity against COVID-19 by remembering and killing the virus if it is reintroduced. Blood samples will also be collected for research purposes. This is a dose-escalation study of ex-vivo knocked-out, expanded, and selected PD-1 knockout-T cells from autologous origin. Patients are assigned to 1 of 3 treatment groups to determine the maximal tolerant dose. After the lower number of cycles are considered tolerant, an arm of the next higher number of cycles will be open to next patients. Biomarkers and immunological markers are collected and analyzed as well. According to the investigator, exhausted virus-reactive CD8+ memory T cells will be isolated from patients with mild infection using a modified antigen-reactive T cell enrichment (ARTE) assay. exhausted virus-reactive CD8+ memory T cells will be collected and Programmed cell death protein 1(PDCD1) gene will be knocked out by CRISPR Cas9 in the laboratory (PD-1 Knockout T cells). The lymphocytes will be selected and expanded ex vivo and infused back into patients. A total of 2 x 10^7/kg PD-1 Knockout T cells will be infused in one cycle. Each cycle is divided into three administrations, with 20% infused in the first administration, 30% in the second, and the remaining 50% in the third. Patients will receive a total of two cycles of treatment.

Last updated: Apr. 20, 2024
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