Skip to content Skip to main navigation Skip to footer

Branch

FDA approves Bristol Myers’ liver cancer therapy

Bristol-Myers-Squibb

(Reuters) – Bristol Myers Squibb’s combination of its immunotherapies, Opdivo and Yervoy, to treat a type of liver cancer received U.S. regulatory approval, the drugmaker said on Wednesday.

The therapy received the Food and Drug Administration’s accelerated approval to treat patients with hepatocellular carcinoma, who have previously been administered sorafenib, the current standard of care. (reut.rs/2xoHuvv)

The accelerated approval program allows a speedier market entry to medicines that fill an unmet medical need for a serious condition, and further clinical trials may be required for final approval of the therapy.

The FDA approval is based on an early stage trial in which 33% of patients responded to the therapy.

“The incidence of liver cancer is rising in the United States…and today’s approval provides a new option for patients with HCC (hepatocellular carcinoma),” said Andrea Wilson, president Blue Faery: The Adrienne Wilson Liver Cancer Association.

HCC is the most common type of primary liver cancer and is more common in people who drink large amounts of alcohol and who have an accumulation of fat in the liver.

via – Reuters | SourceReuters | Search  》liver cancer therapy

Doctors Try 1st CRISPR Editing in the Body for Blindness

Genetic Frontiers Gene Editing Blindness
Dr. Jason Comander, inherited retinal disorder specialist at Massachusetts Eye and Ear Infirmary in Boston points to a model of an eye during an interview on Jan. 8, 2020. Comander's hospital plans to enroll patients in a gene editing treatment for blindness study. He said it marks “a new era in medicine” using a technology that “makes editing DNA much easier and much more effective.” (AP Photo/Rodrique Ngowi)

Scientists say they have used the gene editing tool CRISPR inside someone’s body for the first time, a new frontier for efforts to operate on DNA, the chemical code of life, to treat diseases.

A patient recently had it done at the Casey Eye Institute at Oregon Health & Science University in Portland for an inherited form of blindness, the companies that make the treatment announced Wednesday. They would not give details on the patient or when the surgery occurred.

It may take up to a month to see if it worked to restore vision. If the first few attempts seem safe, doctors plan to test it on 18 children and adults.

“We literally have the potential to take people who are essentially blind and make them see,” said Charles Albright, chief scientific officer at Editas Medicine, the Cambridge, Massachusetts-based company developing the treatment with Dublin-based Allergan. “We think it could open up a whole new set of medicines to go in and change your DNA.”

Dr. Jason Comander, an eye surgeon at Massachusetts Eye and Ear in Boston, another hospital that plans to enroll patients in the study, said it marks “a new era in medicine” using a technology that “makes editing DNA much easier and much more effective.”

Doctors first tried in-the-body gene editing in 2017 for a different inherited disease using a tool called zinc fingers. Many scientists believe CRISPR is a much easier tool for locating and cutting DNA at a specific spot, so interest in the new research is very high.

The people in this study have Leber congenital amaurosis, caused by a gene mutation that keeps the body from making a protein needed to convert light into signals to the brain, which enables sight. They’re often born with little vision and can lose even that within a few years.

Scientists can’t treat it with standard gene therapy — supplying a replacement gene — because the one needed is too big to fit inside the disabled viruses that are used to ferry it into cells.

So they’re aiming to edit, or delete the mutation by making two cuts on either side of it. The hope is that the ends of DNA will reconnect and allow the gene to work as it should.

It’s done in an hour-long surgery under general anesthesia. Through a tube the width of a hair, doctors drip three drops of fluid containing the gene editing machinery just beneath the retina, the lining at the back of the eye that contains the light-sensing cells.

“Once the cell is edited, it’s permanent and that cell will persist hopefully for the life of the patient,” because these cells don’t divide, said one study leader not involved in this first case, Dr. Eric Pierce at Massachusetts Eye and Ear.

Doctors think they need to fix one tenth to one third of the cells to restore vision. In animal tests, scientists were able to correct half of the cells with the treatment, Albright said.

The eye surgery itself poses little risk, doctors say. Infections and bleeding are relatively rare complications.

One of the biggest potential risks from gene editing is that CRISPR could make unintended changes in other genes, but the companies have done a lot to minimize that and to ensure that the treatment cuts only where it’s intended to, Pierce said. He has consulted for Editas and helped test a gene therapy, Luxturna, that’s sold for a different type of inherited blindness.

Some independent experts were optimistic about the new study.

“The gene editing approach is really exciting. We need technology that will be able to deal with problems like these large genes,” said Dr. Jean Bennett, a University of Pennsylvania researcher who helped test Luxturna at the Children’s Hospital of Philadelphia.

In one day, she had three calls from families seeking solutions to inherited blindness.

“It’s a terrible disease,” she said. “Right now they have nothing.”

Dr. Kiran Musunuru, another gene editing expert at the University of Pennsylvania, said the treatment seems likely to work, based on tests in human tissue, mice and monkeys.

The gene editing tool stays in the eye and does not travel to other parts of the body, so “if something goes wrong, the chance of harm is very small,” he said. “It makes for a good first step for doing gene editing in the body.”

Although the new study is the first to use CRISPR to edit a gene inside the body, another company, Sangamo Therapeutics, has been testing zinc finger gene editing to treat metabolic diseases.

Other scientists are using CRISPR to edit cells outside the body to try to treat cancer, sickle cell and some other diseases.

All of these studies have been done in the open, with government regulators’ approval, unlike a Chinese scientist’s work that brought international scorn in 2018. He Jiankui used CRISPR to edit embryos at the time of conception to try to make them resistant to infection with the AIDS virus. Changes to embryos’ DNA can pass to future generations, unlike the work being done now in adults to treat diseases.

via – VOA | Source – VOA | Search  》CRISPR Gene Editing

The eyes are the window to spotting early signs of dementia

As the population of the West ages. New innovations in detecting early signs of Dementia are being explored.

early-signs-dementia-eyes
A look within. (Reuters/Noor Khamis)

As our body’s central control center, the brain has to keep going at all costs. It makes sense that it’s surrounded by biological safeguards: a bony skull, a sack of tissue, and blood vessels that filter out most infectious bugs. When neurons start to decline—as some do naturally with age—the brain can even quickly rewire networks before we notice anything is amiss.

But these same safeguards are a huge obstacle for scientists trying to study the brain’s decline—specifically dementia. Grey matter is excellent at adapting to the slow buildup of abnormal proteins, the cause of several forms of dementia, and it lacks the same pain receptors as the rest of our body. So by the time a patient starts becoming forgetful, or having trouble concentrating, the cellular damage is already substantial—and usually irreversible.

In order to slow or prevent dementia, scientists will have to be able to spot it before cognitive systems collapse. Current diagnostic tools for Alzheimer’s, the most common form of dementia, can confirm the build-ups of misshapen amyloid-beta or tau, the hallmarks of the condition. But they are both expensive (PET scans) and painfully invasive (spinal taps). Blood tests are a promising strategy, though after years of research scientists are still struggling to distinguish the chemical signs of normal aging from the signs of dementia.

So a smaller contingent of researchers are trying a novel strategy. They’re looking instead at changes in our sight—a complex sense with several processing steps, each one providing an opportunity for scientists to capture a blip that signals impending doom for the brain. This research is in its infancy. But with the population of aging adults at risk for dementia increasing daily, it’s a critical route of exploration.

The eyes have it

Vision requires our eyes to collect information and send it to the brain, where an entire region works to interpret it in fewer than 120 milliseconds (paywall) by some estimates.

The first stop is the eye—specifically the retina, which picks up images for the brain to interpret. “The retina is a direct extension of your brain,” says Sandra Weintraub, a neurologist at Northwestern University’s School of Medicine. “It actually has neuronal cells.” When something is wrong in the brain, the retina could reflect that damage as inflammation damages tiny blood vessels, called capillaries, around its neuronal cells.

Weintraub thinks that lower capillary counts could help indicate the early signs of dementia. In April of this year, she and her colleague Amani Fawzi, an ophthalmologist also at Northwestern, published work showing noticeable differences in the retinal blood vessels of individuals with mild cognitive impairment or early Alzheimer’s disease and healthy individuals. People with cognitive impairment had fewer capillaries in their retina than those who did not.

It was a small study: just 32 people total, half of them with symptoms of cognitive decline and the others healthy. That’s not enough data to predict if a person is in the early stages of dementia. In order to strengthen this research, Weintraub’s team will next look at a larger group of individuals—preferably with a wider set of ages, and at different stages of progressing dementia.

Making sense of sight

In addition to the eye itself, the brain’s interpretation of images could also serve as an indication of brain health. “The eye isn’t a camera,” says Alyssa Brewer, a neuroscientist at the University of California, Irvine. “The brain fills in all kinds of info based on prior experience and expectation about how things normally look.” This trick likely has an evolutionary purpose: It makes it much easier for us to quickly suss out our environment, and in particular to pick out faces. (This is also why it’s common for us to find faces in objects that are not human, or even animals.)

 

Changes in the way our brains make sense of the visual world can indicate a larger neurological change. That’s why Brewer studies the brain’s visual cortex, where the bulk of our image processing happens. In particular, she looks at the way regions of the visual cortex are organized into so-called visual field maps. In a small study published in 2014, she and her team used magnetic resonance imaging to compare the visual cortices of a handful of college students, healthy older adults, and two adults of the same age who had been diagnosed with mild Alzheimer’s disease. Although the participants with Alzheimer’s had normal vision, “their maps were completely disordered,” Brewer says. “We were definitely surprised the level of changes that were happening very early on in Alzheimer’s.”

That work measured participants’ visual status quo. By extension, one way to detect early changes in the brain’s visual capacity would be to challenge the system with a hard task—like spotting animals in black and white images flashed for a hundredth of a second on screen.

That’s the idea that London-based start-up Cognetivity is betting on. In January of this year, their research team published work in the journal Nature Scientific Reports showing that their technique could be used as part of cognitive health assessments given in doctors’ offices, although they have yet to be given clearance for clinical use. Tom Sawyer, Cognetivity’s chief operating officer, told Quartz that the company is hoping to run the test on larger populations, including people who have depression or multiple sclerosis, to try to identify subtle changes in visual cognition common among neurological conditions.

Although these are all good leads for better diagnostic tests, they have one problem in common: There’s too much person-to-person variability in eye structure, cortex organization, and visual processing to create a static metric for brain health, the way there is for blood pressure. “We don’t have a good enough handle of what ‘normal’ is in many aspects, even in vision,” says Brewer.

That said, simpler ways of taking snapshots of the brain’s health could make it easier for health care providers to track their patients’ progress over time—and note any seriously concerning dips in cognitive abilities. Even if these tests couldn’t diagnose a specific form of dementia, they could cue health care providers to order tests like PET scans or spinal taps for their patients sooner. Having an earlier diagnosis before their symptoms progress makes it easier for patients and loved ones to plan for the care they’ll need, and it opens the door for them to be enrolled in potentially beneficial clinical trials.

via – Quartz | Source – Quartz | Search  》Dementia Alzheimers Diagnosis