A Chinese team of researchers, led by oncologist Lu You at Sichuan University in Chengdu, delivered CRISPR-modified cells into a patient with aggressive lung cancer, as part of a clinical trial at West China Hospital, Chengdu, for the first time in the world on 28 October.

The genes were edited using the revolutionary CRISPR-Cas9 technique, a simpler and more efficient technique compared to others, and deemed to accelerate the race to get gene-edited cells into clinics across the world, said Carl June, a researcher at the University of Pennsylvania who led earlier clinical studies that used different cell-editing techniques.

"I think this is going to trigger 'Sputnik 2.0', a biomedical duel on progress between China and the United States, which is important since competition usually improves the end product," he says.

Lu's trial received ethical approval from a hospital review board in July and injections were supposed to begin in August but were postponed because the culturing and amplifying the cells took longer than expected. When they were ready, the team ran into China's October holidays and just needed to wait, Lu says.

Editing cells to turn onto cancer cells

The researchers have removed immune cells from the recipient's blood and disabled a gene using CRISPR-Cas9. The disabled gene codes for protein PD-1 that halts the cell's immune response, and cancers take the chance to proliferate.

Lu's team then cultured the edited cells, amplified them in number and injected them back into the patient who suffers from metastatic non-small-cell lung cancer. The hope is for the edited cells to attack and defeat the cancer.

As of now, Lu says that treatment has been smooth so far and the patient is scheduled for a second injection. No details have been disclosed because of patient confidentiality. The team plans to treat a total of ten people, who will each receive a range of two to four injections.

Mainly a safety trial

The trial is primarily a safety trial and participants are monitored for six months to determine side effects, if any. They will still be monitored past six months to see if the treatment is beneficial.

Many oncologists are excited about CRISPR's entry into the cancer treatment scene.

"The technology to be able to do this is incredible," says Naiyer Rizvi of Columbia University Medical Center in New York City.

Antibodies that neutralise PD-1 have shown to successfully put lung cancer in check, Antonio Russo of Palermo University in Italy said. The CRISPR-enabled attack on the protein might work as "the rationale is strong", he added.

Whether this particular trial succeeds or not, still remains to be seen as much like precision or personalised medicine, the process of extracting, genetically modifying and multiplying cells is "a huge undertaking and not very scalable", Rizvi says.

"Unless it shows a large gain in efficacy, it will be hard to justify moving forwards," he said.

There are doubts that this process will be superior to the use of antibodies, which can be expanded to unlimited quantities in the clinic. Lu says that this question is being evaluated in the trial, but that it is too early to say which approach is better. MIMS

Read more:
12-year-old girl solves longstanding gene mutation issue with code
Are we over-propagandising genetic research?
New DNA alteration technology developed by Singapore scientists