When Jane Stein and her husband used in-vitro fertilization in 2001 to become pregnant with twins, her fertility clinic recommended using a supplemental procedure called intracytoplasmic sperm injection (ICSI), known in fertility lingo as "ix-see."
'Add-on' fertility procedures are increasingly coming under scrutiny for having a high cost and low efficacy rate.
During IVF, an egg and sperm are placed in a petri dish together with the hope that a sperm will seek out and fertilize the egg. With ICSI, doctors inject sperm directly into the egg.
Stein, whose name has been changed to protect her privacy, agreed to try it. Her twins are now 16, but while 17 years have gone by since that procedure, the efficacy of ICSI is still unclear. In other words, while Stein succeeded in having children, it may not have been because of ICSI. It may simply have been because she did IVF.
The American Society for Reproductive Medicine has concluded, "There are no data to support the routine use of ICSI for non-male factor infertility." That is, ICSI can help couples have a baby when the issue is male infertility. But when it's not, the evidence of its effectiveness is lacking. And yet the procedure is being used more and more, even when male infertility is not the issue. Some 40 percent of fertility treatments in Europe, Asia and the Middle East now use ICSI, according to a world report released in 2016 by the International Committee for Monitoring Assisted Reproductive Technologies. In the Middle East, the figure is actually 100 percent, the report said.
ICSI is just one of many supplemental procedures, or 'add-ons,' increasingly coming under scrutiny for having a high cost and low efficacy rate. They cost anywhere from a couple of hundred dollars to several thousand – ICSI costs $2,000 to $3,000 -- hiking up the price of what is already a very costly endeavor. And many don't even work. Worse, some actually cause harm.
It's no surprise couples use them. They promise to increase the chance of conceiving. For patients who desperately want a child, money is no object. The Human Fertilization and Embryology Authority (HFEA) in the U.K. found that some 74 percent of patients who received fertility treatments over the last two years were given at least one type of add-on. Now, fertility associations in the U.S. and abroad have begun issuing guidance about which add-ons are worth the extra cost and which are not.
"Many IVF add-ons have little in the way of conclusive evidence supporting their role in successful IVF treatment," said Professor Geeta Nargund, medical director of CREATE Fertility and Lead Consultant for reproductive medicine at St George's Hospital, London.
The HFEA has actually rated these add-ons, indicating which procedures are effective and safe. Some treatments were rated 'red' because they were considered to have insufficient evidence to justify their use. These include assisted hatching, which uses acid or lasers to make a hole in the surrounding layer of proteins to help the embryo hatch; intrauterine culture, where a device is inserted into the womb to collect and incubate the embryo; and reproductive immunology, which suppresses the body's natural immunity so that it accepts the embryo.
"Fertility care is a highly competitive market. In a private system, offering add-ons may discern you from your neighboring clinic."
For some treatments, the HFEA found there is evidence that they don't just fail to work, but can even be harmful. These procedures include ICSI used when male infertility is not at issue, as well as a procedure called endometrial scratching, where the uterus is scratched, not unlike what would happen with a biopsy, to stimulate the local uterine immune system.
And then for some treatments, there is conflicting evidence, warranting further research. These include artificial egg activation by calcium ionophore, elective freezing in all cycles, embryo glue, time-lapse imaging and pre-implantation genetic testing for abnormal chromosomes on day 5.
"Currently, there is very little evidence to suggest that many of the add-ons could increase success rates," Nargund said. "Indeed, the HFEA's assessment of add-on treatments concluded that none of the add-ons could be given a 'green' rating, due to a lack of conclusive supporting research."
So why do fertility clinics offer them?
"Fertility care is a highly competitive market," said Professor Hans Evers, editor-in-chief of the journal Human Reproduction. "In a private system, offering add-ons may discern you from your neighboring clinic. The more competition, the more add-ons. Hopefully the more reputable institutions will only offer add-ons (for free) in the context of a randomized clinical trial."
The only way for infertile couples to know which work and which don't is the guidance released by professional organizations like the ASRM, and through government regulation in countries that have a public health care system.
The problem is, infertile couples will sometimes do anything to achieve a pregnancy.
"They will stand on their heads if this is advocated as helpful. Someone has to protect them," Evers said.
In the Netherlands, where Evers is based, the national health care system tries to make the best use of the limited resources it has, so it makes sure the procedures it's funding actually work, Evers said.
"We have calculated that to serve a population of 17 million, we need 13 IVF clinics, and we have 13," he said. "We as professionals discuss and try to agree on the value of newly proposed add-ons, and we will implement only those that are proven effective and safe."
Likewise, in the U.K., there's been a lot of squawking about speculative add-ons because the government, or National Health Service, pays for them. In the U.S., it's private insurers or patients' own cash.
"The [U.K.] government takes a very close look at what therapies they are offering and what the evidence is around offering the therapy," said Alan Penzias, who chairs the Practice Committee of the ASRM. It wants to make sure the treatments it is funding are at least worth the money.
ICSI is a case in point. Originally intended for male infertility, it's now being applied across the board because fertility clinics didn't want couples to pay $10,000 to $15,000 and wind up with no embryos.
"It is so disastrous to have no fertilization whatsoever, clinics started to make this bargain with their patients, saying, 'Well, listen, even though it's not indicated, what we would like to do is to take half of your eggs and do the ICSI procedure, and half we'll do conventional insemination just to make sure,'" he said. "It's a disaster if you have no embryos, and now you're out 10 to 12 thousand dollars, so for a small added fee, we can do the injection just to guard against that."
In the Netherlands, the national health care system tries to make the best use of its limited resources, so it makes sure the procedures it's funding actually work.
Clinics offer it where they see lower rates of fertilization, such as with older women or in cases where induced ovulation results in just two or three eggs instead of, say, 13. Unfortunately, ICSI may result in a higher fertilization rate, but it doesn't result in a higher live birth rate, according to a study last year in Human Reproduction, so couples wind up paying for a procedure that doesn't even result in a child.
Private insurers in the U.S. are keen to it. Penzia, who is also an associate professor of obstetrics, gynecology and reproductive biology at Harvard Medical School and works as a reproductive endocrinology and infertility specialist at Boston IVF, said Massachusetts requires that insurers cover infertility treatments. But when he submits claims for ICSI, for instance, insurers now want to see two sperm counts and proof that the man has seen a urologist.
"They want to make sure we're doing it for male factor (infertility)," he said. "That's not unreasonable, because the insurance company is taking the burden of this."
In November 2020, messenger RNA catapulted into the public consciousness when the first COVID-19 vaccines were authorized for emergency use. Around the same time, an equally groundbreaking yet relatively unheralded application of mRNA technology was taking place at a London hospital.
Over the past two decades, there's been increasing interest in harnessing mRNA — molecules present in all of our cells that act like digital tape recorders, copying instructions from DNA in the cell nucleus and carrying them to the protein-making structures — to create a whole new class of therapeutics.
Scientists realized that artificial mRNA, designed in the lab, could be used to instruct our cells to produce certain antibodies, turning our bodies into vaccine-making factories, or to recognize and attack tumors. More recently, researchers recognized that mRNA could also be used to make another groundbreaking technology far more accessible to more patients: gene editing. The gene-editing tool CRISPR has generated plenty of hype for its potential to cure inherited diseases. But delivering CRISPR to the body is complicated and costly.
"Most gene editing involves taking cells out of the patient, treating them and then giving them back, which is an extremely expensive process," explains Drew Weissman, professor of medicine at the University of Pennsylvania, who was involved in developing the mRNA technology behind the COVID-19 vaccines.
But last November, a Massachusetts-based biotech company called Intellia Therapeutics showed it was possible to use mRNA to make the CRISPR system inside the body, eliminating the need to extract cells out of the body and edit them in a lab. Just as mRNA can instruct our cells to produce antibodies against a viral infection, it can also teach them to produce the two molecular components that make up CRISPR — a guide molecule and a cutting protein — to snip out a problem gene.
"The pandemic has really shown that not only are mRNA approaches viable, they could in certain circumstances be vastly superior to more traditional technologies."
In Intellia's London-based clinical trial, the company applied this for the first time in a patient with a rare inherited liver disease known as hereditary transthyretin amyloidosis with polyneuropathy. The disease causes a toxic protein to build up in a person's organs and is typically fatal. In a company press release, Intellia's president and CEO John Leonard swiftly declared that its mRNA-based CRISPR therapy could usher in a "new era of potential genome editing cures."
Weissman predicts that turning CRISPR into an affordable therapy will become the next major frontier for mRNA over the coming decade. His lab is currently working on an mRNA-based CRISPR treatment for sickle cell disease. More than 300,000 babies are born with sickle cell every year, mainly in lower income nations.
"There is a FDA-approved cure, but it involves taking the bone marrow out of the person, and then giving it back which is prohibitively expensive," he says. It also requires a patient to have a matched bone marrow done. "We give an intravenous injection of mRNA lipid nanoparticles that target CRISPR to the bone marrow stem cells in the patient, which is easy, and much less expensive."
Meanwhile, the overwhelming success of the COVID-19 vaccines has focused attention on other ways of using mRNA to bolster the immune system against threats ranging from other infectious diseases to cancer.
The practicality of mRNA vaccines – relatively small quantities are required to induce an antibody response – coupled with their adaptable design, mean companies like Moderna are now targeting pathogens like Zika, chikungunya and cytomegalovirus, or CMV, which previously considered commercially unviable for vaccine developers. This is because outbreaks have been relatively sporadic, and these viruses mainly affect people in low-income nations who can't afford to pay premium prices for a vaccine. But mRNA technology means that jabs could be produced on a flexible basis, when required, at relatively low cost.
Other scientists suggest that mRNA could even provide a means of developing a universal influenza vaccine, a goal that's long been the Holy Grail for vaccinologists around the world.
"The mRNA technology allows you to pick out bits of the virus that you want to induce immunity to," says Michael Mulqueen, vice president of business development at eTheRNA, a Belgium-based biotech that's developing mRNA-based vaccines for malaria and HIV, as well as various forms of cancer. "This means you can get the immune system primed to the bits of the virus that don't vary so much between strains. So you could actually have a single vaccine that protects against a whole raft of different variants of the same virus, offering more universal coverage."
Before mRNA became synonymous with vaccines, its biggest potential was for cancer treatments. BioNTech, the German biotech company that collaborated with Pfizer to develop the first authorized COVID-19 vaccine, was initially founded to utilize mRNA for personalized cancer treatments, and the company remains interested in cancers ranging from melanoma to breast cancer.
One of the major hurdles in treating cancer has been the fact that tumors can look very different from one person to the next. It's why conventional approaches, such as chemotherapy or radiation, don't work for every patient. But weaponizing mRNA against cancer primes the immune cells with the tumor's specific genetic sequence, training the patient's body to attack their own unique type of cancer.
"It means you're able to think about personalizing cancer treatments down to specific subgroups of patients," says Mulqueen. "For example, eTheRNA are developing a renal cell carcinoma treatment which will be targeted at around 20% of these patients, who have specific tumor types. We're hoping to take that to human trials next year, but the challenge is trying to identify the right patients for the treatment at an early stage."
Repairing Damaged mRNA
While hopes are high that mRNA could usher in new cancer treatments and make CRISPR more accessible, a growing number of companies are also exploring an alternative to gene editing, known as RNA editing.
In genetic disorders, the mRNA in certain cells is impaired due to a rogue gene defect, and so the body ceases to produce a particular vital protein. Instead of permanently deleting the problem gene with CRISPR, the idea behind RNA editing is to inject small pieces of synthetic mRNA to repair the existing mRNA. Scientists think this approach will allow normal protein production to resume.
Over the past few years, this approach has gathered momentum, as some researchers have recognized that it holds certain key advantages over CRISPR. Companies from Belgium to Japan are now looking at RNA editing to treat all kinds of disorders, from Huntingdon's disease, to amyotrophic lateral sclerosis, or ALS, and certain types of cancer.
"With RNA editing, you don't need to make any changes to the DNA," explains Daniel de Boer, CEO of Dutch biotech ProQR, which is looking to treat rare genetic disorders that cause blindness. "Changes to the DNA are permanent, so if something goes wrong, that may not be desirable. With RNA editing, it's a temporary change, so we dose patients with our drugs once or twice a year."
Last month, ProQR reported a landmark case study, in which a patient with a rare form of blindness called Leber congenital amaurosis, which affects the retina at the back of the eye, recovered vision after three months of treatment.
"We have seen that this RNA therapy restores vision in people that were completely blind for a year or so," says de Boer. "They were able to see again, to read again. We think there are a large number of other genetic diseases we could go after with this technology. There are thousands of different mutations that can lead to blindness, and we think this technology can target approximately 25% of them."
Ultimately, there's likely to be a role for both RNA editing and CRISPR, depending on the disease. "I think CRISPR is ideally suited for illnesses where you would like to permanently correct a genetic defect," says Joshua Rosenthal of the Marine Biology Laboratory in Chicago. "Whereas RNA editing could be used to treat things like pain, where you might want to reset a neural circuit temporarily over a shorter period of time."
Much of this research has been accelerated by the COVID-19 pandemic, which has played a major role in bringing mRNA to the forefront of people's minds as a therapeutic.
"The pandemic has really shown that not only are mRNA approaches viable, they could in certain circumstances be vastly superior to more traditional technologies," says Mulqueen. "In the future, I would not be surprised if many of the top pharma products are mRNA derived."
"Making Sense of Science" is a monthly podcast that features interviews with leading medical and scientific experts about the latest developments and the big ethical and societal questions they raise. This episode is hosted by science and biotech journalist Emily Mullin, summer editor of the award-winning science outlet Leaps.org.