Why Don’t We Have Artificial Wombs for Premature Infants?
A lamb which was prematurely born at the equivalent of 23 weeks' human gestation, after 28 days of support from an artificial womb.
Ectogenesis, the development of a baby outside of the mother's body, is a concept that dates back to 1923. That year, British biochemist-geneticist J.B.S. Haldane gave a lecture to the "Heretics Society" of the University of Cambridge in which he predicted the invention of an artificial womb by 1960, leading to 70 percent of newborns being born that way by the 2070s. In reality, that's about when an artificial womb could be clinically operational, but trends in science and medicine suggest that such technology would come in increments, each fraught with ethical and social challenges.
An extra-uterine support device could be ready for clinical trials in humans in the next two to four years, with hopes that it could improve survival of very premature infants.
Currently, one major step is in the works, a system called an extra-uterine support device (EUSD) –or sometimes Ex-Vivo uterine Environment (EVE)– which researchers at the Children's Hospital of Philadelphia have been using to support fetal lambs outside the mother. It also has been called an artificial placenta, because it supplies nutrient- and oxygen-rich blood to the developing lambs via the umbilical vein and receives blood full of waste products through the umbilical arteries. It does not do everything that a natural placenta does, yet it does do some things that a placenta doesn't do. It breathes for the fetus like the mother's lungs, and encloses the fetus in sterile fluid, just like the amniotic sac. It represents a solution to one set of technical challenges in the path to an artificial womb, namely how to keep oxygen flowing into a fetus and carbon dioxide flowing out when the fetal lungs are not ready to function.
Capable of supporting fetal lambs physiologically equivalent to a human fetus at 23 weeks' gestation or earlier, the EUSD could be ready for clinical trials in humans in the next two to four years, with hopes that it could improve survival of very premature infants. Existing medical technology can keep human infants alive when born in this 23-week range, or even slightly less —the record is just below 22 weeks. But survival is low, because most of the treatment is directed at the lungs, the last major body system to mature to a functional status. This leads to complications not only in babies born before 24 weeks' gestation, but also in a fairly large number of births up to 28 weeks' gestation.
So, the EUSD is basically an advanced neonatal life support machine that beckons to square off the survival curve for infants born up to the 28th week. That is no doubt a good thing, but given the political prominence of reproductive issues, might any societal obstacles be looming?
"While some may argue that the EUSD system will shift the definition of viability to a point prior to the maturation of the fetus' lungs, ethical and legal frameworks must still recognize the mother's privacy rights as paramount."
Health care attorney and clinical ethicist David N. Hoffman points out that even though the EUSD may shift the concept of fetal viability away from the maturity of developing lungs, it would not change the current relationship of the fetus to the mother during pregnancy.
"Our social and legal frameworks, including Roe v. Wade, invite the view of the embryo-fetus as resembling a parasite. Not in a negative sense, but functionally, since it obtains its life support from the mother, while she does not need the fetus for her own physical health," notes Hoffman, who holds faculty appointments at Columbia University, and at the Benjamin N. Cardozo School of Law and the Albert Einstein College of Medicine, of Yeshiva University. "In contrast, our ethical conception of the relationship is grounded in the nurturing responsibility of parenthood. We prioritize the welfare of both mother and fetus ethically, but we lean toward the side of the mother's legal rights, regarding her health throughout pregnancy, and her right to control her womb for most of pregnancy. While some may argue that the EUSD system will shift the definition of viability to a point prior to the maturation of the fetus' lungs, ethical and legal frameworks must still recognize the mother's privacy rights as paramount, on the basis of traditional notions of personhood and parenthood."
Outside of legal frameworks, religion, of course, is a major factor in how society reacts to new reproductive technologies, and an artificial womb would trigger a spectrum of responses.
"Significant numbers of conservative Christians may oppose an artificial womb in fear that it might harm the central role of marriage in Christianity."
Speaking from the perspective of Lutheran scholarship, Dr. Daniel Deen, Assistant Professor of Philosophy at Concordia University in Irvine, Calif., does not foresee any objections to the EUSD, either theologically, or generally from Lutherans (who tend to be conservative on reproductive issues), since the EUSD is basically an improvement on current management of prematurity. But things would change with the advent of a full-blown artificial womb.
"Significant numbers of conservative Christians may oppose an artificial womb in fear that it might harm the central role of marriage in Christianity," says Deen, who specializes in the philosophy of science. "They may see the artificial womb as a catalyst for strengthening the mechanistic view of reproduction that dominates the thinking of secular society, and of other religious groups, including more liberal Christians."
Judaism, however, appears to be more receptive, even during the research phases.
"Even if researchers strive for a next-generation EUSD aimed at supporting a fetus several weeks earlier than possible with the current system, it still keeps the fetus inside the mother well beyond the 40-day threshold, so there likely are no concerns in terms of Jewish law," says Kalman Laufer, a rabbinical student and executive director of the Medical Ethics Society at Yeshiva University. Referring to a concept from the Babylonian Talmud that an embryo is "like water" until 40 days into pregnancy, at which time it receives a kind of almost-human status warranting protection, Laufer cautions that he's speaking about artificial wombs developed for the sake of rescuing very premature infants. At the same time though, he expects that artificial womb research will eventually trigger a series of complex, legalistic opinions from Jewish scholars, as biotechnology moves further toward supporting fetal growth entirely outside a woman's body.
"Since [the EUSD] gives some justification to end abortion, by transferring fetuses from mother to machine, conservatives will probably rally around it."
While the technology treads into uncomfortable territory for social conservatives at first glance, it's possible that the prospect of taking the abortion debate in a whole new direction could engender support for the artificial womb. "Since [the EUSD] gives some justification to end abortion, by transferring fetuses from mother to machine, conservatives will probably rally around it," says Zoltan Istvan, a transhumanist politician and journalist who ran for U.S. president in 2016. To some extent, Deen agrees with Istvan, provided we get to a point when the artificial womb is already a reality.
"The world has a way of moving forward despite the fear of its inhabitants," Deen notes. "If the technology gets developed, I could not see any Christians, liberal or conservative, arguing that people seeking abortion ought not opt for a 'transfer' versus an abortive procedure."
So then how realistic is a full-blown artificial womb? The researchers at the Children's Hospital of Philadelphia have noted various technical difficulties that would come up in any attempt to connect a very young fetus to the EUSD and maintain life. One issue is the small umbilical cord blood vessels that must be connected to the EUSD as fetuses of decreasing gestational age are moved outside the mother. Current procedures might be barely adequate for integrating a human fetus into the device in the 18 -21 week range, but going to lower gestational ages would require new technology and different strategies. It also would require numerous other factors to cover for fetal body systems that mature ahead of the lungs and that the current EUSD system is not designed to replace. However, biotechnology and tissue engineering strategies on the horizon could be added to later EUSDs. To address the blood vessel size issue, artificial womb research could benefit by drawing on experts in microfluidics, the field concerned with manipulation of tiny amounts of fluid through very small spaces, and which is ushering in biotech innovations like the "lab on a chip".
"The artificial womb might put fathers on equal footing with mothers, since any embryo could potentially achieve personhood without ever seeing the inside of a woman's uterus."
If the technical challenges to an artificial womb are indeed overcome, reproductive policy debates could be turned on their side.
"Evolution of the EUSD into a full-blown artificial external uterus has ramifications for any reproductive rights issues where policy currently assumes that a mother is needed for a fertilized egg to become a person," says Hoffman, the ethicist and legal scholar. "If we consider debates over whether to keep cryopreserved human embryos in storage, destroy them, or utilize them for embryonic stem cell research or therapies, the artificial womb might put fathers on equal footing with mothers, since any embryo could potentially achieve personhood without ever seeing the inside of a woman's uterus."
Such a scenario, of course, depends on today's developments not being curtailed or sidetracked by societal objections before full-blown ectogenesis is feasible. But if this does ever become a reality, the history of other biotechnologies suggests that some segment of society will embrace the new innovation and never look back.
Questions remain about new drug for hot flashes
In May, a new drug, Fezolinetant, was approved by the FDA to treat hot flashes associated with menopause.
Vascomotor symptoms (VMS) is the medical term for hot flashes associated with menopause. You are going to hear a lot more about it because a company has a new drug to sell. Here is what you need to know.
Menopause marks the end of a woman’s reproductive capacity. Normal hormonal production associated with that monthly cycle becomes erratic and finally ceases. For some women the transition can be relatively brief with only modest symptoms, while for others the body's “thermostat” in the brain is disrupted and they experience hot flashes and other symptoms that can disrupt daily activity. Lifestyle modification and drugs such as hormone therapy can provide some relief, but women at risk for cancer are advised not to use them and other women choose not to do so.
Fezolinetant, sold by Astellas Pharma Inc. under the product name Veozah™, was approved by the Food and Drug Administration (FDA) on May 12 to treat hot flashes associated with menopause. It is the first in a new class of drugs called neurokinin 3 receptor antagonists, which block specific neurons in the brain “thermostat” that trigger VMS. It does not appear to affect other symptoms of menopause. As with many drugs targeting a brain cell receptor, it must be taken continuously for a few days to build up a good therapeutic response, rather than working as a rescue product such as an asthma inhaler to immediately treat that condition.
Hot flashes vary greatly and naturally get better or resolve completely with time. That contributes to a placebo effect and makes it more difficult to judge the outcome of any intervention. Early this year, a meta analysis of 17 studies of drug trials for hot flashes found an unusually large placebo response in those types of studies; the placebo groups had an average of 5.44 fewer hot flashes and a 36 percent reduction in their severity.
In studies of fezolinetant, the drug recently approved by the FDA, the placebo benefit was strong and persistent. The drug group bested the placebo response to a statistically significant degree but, “If people have gone from 11 hot flashes a day to eight or seven in the placebo group and down to a couple fewer ones in the drug groups, how meaningful is that? Having six hot flashes a day is still pretty unpleasant,” says Diana Zuckerman, president of the National Center for Health Research (NCHR), a health oriented think tank.
“Is a reduction compared to placebo of 2-3 hot flashes per day, in a population of women experiencing 10-11 moderate to severe hot flashes daily, enough relief to be clinically meaningful?” Andrea LaCroix asked a commentary published in Nature Medicine. She is an epidemiologist at the University of California San Diego and a leader of the MsFlash network that has conducted a handful of NIH-funded studies on menopause.
Questions Remain
LaCroix and others have raised questions about how Astellas, the company that makes the new drug, handled missing data from patients who dropped out of the clinical trials. “The lack of detailed information about important parameters such as adherence and missing data raises concerns that the reported benefits of fezolinetant very likely overestimate those that will be observed in clinical practice," LaCroix wrote.
In response to this concern, Anna Criddle, director of global portfolio communications at Astellas, wrote in an email to Leaps.org: “…a full analysis of data, including adherence data and any impact of missing data, was submitted for assessment by [the FDA].”
The company ran the studies at more than 300 sites around the world. Curiously, none appear to have been at academic medical centers, which are known for higher quality research. Zuckerman says, "When somebody is paid to do a study, if they want to get paid to do another study by the same company, they will try to make sure that the results are the results that the company wants.”
Criddle said that Astellas picked the sites “that would allow us to reach a diverse population of women, including race and ethnicity.”
A trial of a lower dose of the drug was conducted in Asia. In March 2022, Astellas issued a press release saying it had failed to prove effectiveness. No further data has been released. Astellas still plans to submit the data, according to Criddle. Results from clinical trials funded by the U.S. goverment must be reported on clinicaltrials.gov within one year of the study's completion - a deadline that, in this case, has expired.
The measurement scale for hot flashes used in the studies, mild-moderate-severe, also came in for criticism. “It is really not good scale, there probably isn’t a broad enough range of things going on or descriptors,” says David Rind. He is chief medical officer of the Institute for Clinical and Economic Review (ICER), a nonprofit authority on new drugs. It conducted a thorough review and analysis of fezolinestant using then existing data gathered from conference abstracts, posters and presentations and included a public stakeholder meeting in December. A 252-page report was published in January, finding “considerable uncertainty about the comparative net health benefits of fezolinetant” versus hormone therapy.
Questions surrounding some of these issues might have been answered if the FDA had chosen to hold a public advisory committee meeting on fezolinetant, which it regularly does for first in class medicines. But the agency decided such a meeting was unnecessary.
Cost
There was little surprise when Astellas announced a list price for fezolinetant of $550 a month ($6000 annually) and a program of patient assistance to ease out of pocket expenses. The company had already incurred large expenses.
In 2017 Astellas purchased the company that originally developed fezolinetant for $534 million plus several hundred million in potential royalties. The drug company ran a "disease awareness” ad, Heat on the Street, hat aired during the Super Bowl in February, where 30 second ads cost about $7 million. Industry analysts have projected sales to be $1.9 billion by 2028.
ICER’s pre-approval evaluation said fezolinetant might "be considered cost-effective if priced around $2,000 annually. ... [It]will depend upon its price and whether it is considered an alternative to MHT [menopause hormone treatment] for all women or whether it will primarily be used by women who cannot or will not take MHT."
Criddle wrote that Astellas set the price based on the novelty of the science, the quality of evidence for the drug and its uniqueness compared to the rest of the market. She noted that an individual’s payment will depend on how much their insurance company decides to cover. “[W]e expect insurance coverage to increase over the course of the year and to achieve widespread coverage in the U.S. over time.”
Leaps.org wrote to and followed up with nine of the largest health insurers/providers asking basic questions about their coverage of fezolinetant. Only two responded. Jennifer Martin, the deputy chief consultant for pharmacy benefits management at the Department of Veterans Affairs, said the agency “covers all drugs from the date that they are launched.” Decisions on whether it will be included in the drug formulary and what if any copays might be required are under review.
“[Fezolinetant] will go through our standard P&T Committee [patient and treatment] review process in the next few months, including a review of available efficacy data, safety data, clinical practice guidelines, and comparison with other agents used for vasomotor symptoms of menopause," said Phil Blando, executive director of corporate communications for CVS Health.
Other insurers likely are going through a similar process to decide issues such as limiting coverage to women who are advised not to use hormones, how much copay will be required, and whether women will be required to first try other options or obtain approvals before getting a prescription.
Rind wants to see a few years of use before he prescribes fezolinetant broadly, and believes most doctors share his view. Nor will they be eager to fill out the additional paperwork required for women to participate in the Astellas patient assistance program, he added.
Safety
Astellas is marketing its drug by pointing out risks of hormone therapy, such as a recent paper in The BMJ, which noted that women who took hormones for even a short period of time had a 24 percent increased risk of dementia. While the percentage was scary, the combined number of women both on and off hormones who developed dementia was small. And it is unclear whether hormones are causing dementia or if more severe hot flashes are a marker for higher risk of developing dementia. This information is emerging only after 80 years of hundreds of millions of women using hormones.
In contrast, the label for fezolinetant prohibits “concomitant use with CYP1A2 inhibitors” and requires testing for liver and kidney function prior to initiating the drug and every three months thereafter. There is no human or animal data on use in a geriatric population, defined as 65 or older, a group that is likely to use the drug. Only a few thousand women have ever taken fezolinetant and most have used it for just a few months.
Options
A woman seeking relief from symptoms of menopause would like to see how fezolintant compares with other available treatment options. But Astellas did not conduct such a study and Andrea LaCroix says it is unlikely that anyone ever will.
ICER has come the closest, with a side-by-side analysis of evidence-based treatments and found that fezolinetant performed quite similarly and modestly as the others in providing relief from hot flashes. Some treatments also help with other symptoms of menopause, which fezolinetant does not.
There are many coping strategies that women can adopt to deal with hot flashes; one of the most common is dressing in layers (such as a sleeveless blouse with a sweater) that can be added or subtracted as conditions require. Avoiding caffeine, hot liquids, and spicy foods is another common strategy. “I stopped drinking hot caffeinated drinks…for several years, and you get out of the habit of drinking them,” says Zuckerman.
LaCroix curates those options at My Meno Plan, which includes a search function where you can enter your symptoms and identify which treatments might work best for you. It also links to published research papers. She says the goal is to empower women with information to make informed decisions about menopause.
A company in England has made a test that picks out the compounds from breath that reveal if people have liver disease.
Every year, around two million people worldwide die of liver disease. While some people inherit the disease, it’s most commonly caused by hepatitis, obesity and alcoholism. These underlying conditions kill liver cells, causing scar tissue to form until eventually the liver cannot function properly. Since 1979, deaths due to liver disease have increased by 400 percent.
The sooner the disease is detected, the more effective treatment can be. But once symptoms appear, the liver is already damaged. Around 50 percent of cases are diagnosed only after the disease has reached the final stages, when treatment is largely ineffective.
To address this problem, Owlstone Medical, a biotech company in England, has developed a breath test that can detect liver disease earlier than conventional approaches. Human breath contains volatile organic compounds (VOCs) that change in the first stages of liver disease. Owlstone’s breath test can reliably collect, store and detect VOCs, while picking out the specific compounds that reveal liver disease.
“There’s a need to screen more broadly for people with early-stage liver disease,” says Owlstone’s CEO Billy Boyle. “Equally important is having a test that's non-invasive, cost effective and can be deployed in a primary care setting.”
The standard tool for detection is a biopsy. It is invasive and expensive, making it impractical to use for people who aren't yet symptomatic. Meanwhile, blood tests are less invasive, but they can be inaccurate and can’t discriminate between different stages of the disease.
In the past, breath tests have not been widely used because of the difficulties of reliably collecting and storing breath. But Owlstone’s technology could help change that.
The team is testing patients in the early stages of advanced liver disease, or cirrhosis, to identify and detect these biomarkers. In an initial study, Owlstone’s breathalyzer was able to pick out patients who had early cirrhosis with 83 percent sensitivity.
Boyle’s work is personally motivated. His wife died of colorectal cancer after she was diagnosed with a progressed form of the disease. “That was a big impetus for me to see if this technology could work in early detection,” he says. “As a company, Owlstone is interested in early detection across a range of diseases because we think that's a way to save lives and a way to save costs.”
How it works
In the past, breath tests have not been widely used because of the difficulties of reliably collecting and storing breath. But Owlstone’s technology could help change that.
Study participants breathe into a mouthpiece attached to a breath sampler developed by Owlstone. It has cartridges are designed and optimized to collect gases. The sampler specifically targets VOCs, extracting them from atmospheric gases in breath, to ensure that even low levels of these compounds are captured.
The sampler can store compounds stably before they are assessed through a method called mass spectrometry, in which compounds are converted into charged atoms, before electromagnetic fields filter and identify even the tiniest amounts of charged atoms according to their weight and charge.
The top four compounds in our breath
In an initial study, Owlstone captured VOCs in breath to see which ones could help them tell the difference between people with and without liver disease. They tested the breath of 46 patients with liver disease - most of them in the earlier stages of cirrhosis - and 42 healthy people. Using this data, they were able to create a diagnostic model. Individually, compounds like 2-Pentanone and limonene performed well as markers for liver disease. Owlstone achieved even better performance by examining the levels of the top four compounds together, distinguishing between liver disease cases and controls with 95 percent accuracy.
“It was a good proof of principle since it looks like there are breath biomarkers that can discriminate between diseases,” Boyle says. “That was a bit of a stepping stone for us to say, taking those identified, let’s try and dose with specific concentrations of probes. It's part of building the evidence and steering the clinical trials to get to liver disease sensitivity.”
Sabine Szunerits, a professor of chemistry in Institute of Electronics at the University of Lille, sees the potential of Owlstone’s technology.
“Breath analysis is showing real promise as a clinical diagnostic tool,” says Szunerits, who has no ties with the company. “Owlstone Medical’s technology is extremely effective in collecting small volatile organic biomarkers in the breath. In combination with pattern recognition it can give an answer on liver disease severity. I see it as a very promising way to give patients novel chances to be cured.”
Improving the breath sampling process
Challenges remain. With more than one thousand VOCs found in the breath, it can be difficult to identify markers for liver disease that are consistent across many patients.
Julian Gardner is a professor of electrical engineering at Warwick University who researches electronic sensing devices. “Everyone’s breath has different levels of VOCs and different ones according to gender, diet, age etc,” Gardner says. “It is indeed very challenging to selectively detect the biomarkers in the breath for liver disease.”
So Owlstone is putting chemicals in the body that they know interact differently with patients with liver disease, and then using the breath sampler to measure these specific VOCs. The chemicals they administer are called Exogenous Volatile Organic Compound) probes, or EVOCs.
Most recently, they used limonene as an EVOC probe, testing 29 patients with early cirrhosis and 29 controls. They gave the limonene to subjects at specific doses to measure how its concentrations change in breath. The aim was to try and see what was happening in their livers.
“They are proposing to use drugs to enhance the signal as they are concerned about the sensitivity and selectivity of their method,” Gardner says. “The approach of EVOC probes is probably necessary as you can then eliminate the person-to-person variation that will be considerable in the soup of VOCs in our breath.”
Through these probes, Owlstone could identify patients with liver disease with 83 percent sensitivity. By targeting what they knew was a disease mechanism, they were able to amplify the signal. The company is starting a larger clinical trial, and the plan is to eventually use a panel of EVOC probes to make sure they can see diverging VOCs more clearly.
“I think the approach of using probes to amplify the VOC signal will ultimately increase the specificity of any VOC breath tests, and improve their practical usability,” says Roger Yazbek, who leads the South Australian Breath Analysis Research (SABAR) laboratory in Flinders University. “Whilst the findings are interesting, it still is only a small cohort of patients in one location.”
The future of breath diagnosis
Owlstone wants to partner with pharmaceutical companies looking to learn if their drugs have an effect on liver disease. They’ve also developed a microchip, a miniaturized version of mass spectrometry instruments, that can be used with the breathalyzer. It is less sensitive but will enable faster detection.
Boyle says the company's mission is for their tests to save 100,000 lives. "There are lots of risks and lots of challenges. I think there's an opportunity to really establish breath as a new diagnostic class.”