A Cure for Sickle Cell Disease Is Coming. Will Patients Accept It?
Many patients in the African-American community are skeptical of new experimental treatments, thanks to a history of medical exploitation in the 20th century.
If any malady proves the fragile grace of the human genome, it is sickle cell disease.
If experimental treatments receive regulatory approval, it would be a watershed breakthrough for tens of thousands of Americans.
It occurs because of a single "misspelled" letter of DNA, causing red blood cells to run low on oxygen and transforming the hemoglobin in each cell into a stiff rod. Normally round cells become rigid crescents that hamper the flow of blood throughout the body, like leaves clumping in a drain.
Strokes in toddlers are merely the beginning of the circulatory calamities this disease may inflict. Most sickled cells cannot carry oxygen through the body, causing anemia as well as excruciating chronic pain. Older patients are at risk of kidney failure, heart disease and all the other collateral damage caused by poor circulation. Few live beyond middle age.
The only way to cure it has been through a bone marrow transplant from a donor, which requires not only a closely matching volunteer, but bouts of chemotherapy to allow new stem cells to take root, as well as rounds of immunosuppressive drugs that may last for years.
Recent advances in genomic medicine may soon alter the disease's outlook, although many obstacles remain.
In one treatment under development, patient's skin cells are converted into stem cells, allowing them to be inserted into the bone marrow without the need for a donor. Another treatment known as gene therapy involves replacing the aberrant gene in the patient's body with new genetic material.
Although both remain in clinical trials -- and also require at least chemotherapy -- they have shown promise. Matthew Hsieh, a hematologist and staff scientist with the National Heart Lung and Blood Institute in Maryland, has performed about 10 gene therapy procedures over the past three years as part of a clinical trial. Ongoing tweaks in the procedure have led to the blood in more recent patients showing sickle cell trait -- not a perfect outcome, but one that leaves patients with far fewer symptoms than if they have the full-blown disease.
If one or both treatments receive regulatory approval, it would be a watershed breakthrough for the tens of thousands of Americans who suffer from the disease.
Yet it is entirely possible many patients may decline the cure.
A Painful History
The vast majority of sickle cell sufferers in the U.S. -- well beyond 90 percent -- are African-American, a population with a historically uneasy relationship toward healthcare.
"There is a lot of data on distrust between African-Americans and American medical institutions," says J. Corey Williams, a psychiatrist with the Children's Hospital of Philadelphia who has written extensively on racial disparities in healthcare. "It comes from a long legacy of feeling victimized by medicine."
"What you hear from many patients is 'I am not going to be your guinea pig, and I am not going to be experimented on.'"
As a result, Williams is among several clinicians interviewed for this story who believe a cure for sickle cell disease would be embraced reluctantly.
"What you hear from many patients is 'I am not going to be your guinea pig, and I am not going to be experimented on.' And so the history of African-Americans and research will manifest as we develop gene therapies for [these] patients," says Christopher L. Edwards, a clinical psychologist and researcher with the Maya Angelou Center for Health Equity at the Wake Forest University School of Medicine.
Fear among African-Americans of becoming guinea pigs is well-founded. The first c-sections and fistula repairs occurring in North America were performed on enslaved women -- all without consent and virtually none with anesthesia.
Modern 20th century medicine led to the Tuskegee syphilis experiments conducted by the U.S. Public Health Service. Researchers withheld treatment from some 400 African-American men from the 1930s well into the 1970s to observe how they reacted to the disease -- even though curative antibiotics had been around for decades. Only news reports ended the experiment.
The long-standing distrust of American healthcare in the African-American community is also baked into the care provided to sickle cell patients. Despite affecting one in 365 African-Americans, there is no disease registry to assist clinical trials, according to Mary Hulihan, a blood disorders epidemiologist with the Centers for Disease Control and Prevention. Edwards says many sufferers are suspicious of being monitored.
Meanwhile, only two drugs are available to alleviate the worst symptoms. The first one, hydroxyurea, received FDA approval only in 1998 -- nearly 90 years after the disease was first diagnosed. Moreover, Edwards says that some sufferers shy away from using hydroxyurea because it is also used to treat cancer. It's part of what he calls the "myth and folklore" in the African-American community about sickle cell disease.
Economics plays a role as well in the often-fragmented care such patients receive. According to CDC data, many patients rely extensively on public insurance programs such as Medicaid, whose coverage varies from state to state.
A Tough Transition
Edwards notes that sickle cell sufferers usually receive good care when they're children because of support provided by family members. But that often breaks down in adulthood. According to CDC data, an adult sickle cell patient visits a hospital emergency room three times as often as a child patient.
The consensus is that the path to a medical cure for sickle cell will first need to be smoothed over with a talk cure.
Modupe Idowu, a hematologist with the University of Texas Health system, estimates that there are perhaps a dozen comprehensive care centers for the estimated 100,000 sickle cell patients in the U.S., including the one she operates in Houston. That means a significant proportion of those afflicted are on their own to procure care.
And since many patients are on Medicaid, "a lot of hematologists that train to take care of blood disorders, many are not interested in treating [sickle cell disease] because the reimbursement for providers is not great," Idowu says.
Hsieh acknowledges that many of his patients can be suspicious about the care they are receiving. Frustration with fragmented care is usually the biggest driver, he adds.
Meanwhile, the skepticism that patients have about the treatments they seek is often reciprocated by their caregivers.
"The patients have experiences with medication and know what works at a very young age (for their pain)," Edwards says. Such expertise demonstrated by an African-American patient often leads to them being labeled as narcotics seekers.
The Correct Path
This all begs the question of how to deploy a cure. Idowu, who regularly holds town hall-style meetings with Houston-area patients, often must allay anxieties. For example, the gene therapy approach uses a harmless virus to transport new genetic material into cells. That virus happens to be a benign version of HIV, and convincing patients they won't be infected with HIV is a fraught issue.
The consensus is that the path to a medical cure for sickle cell will first need to be smoothed over with a talk cure.
Idowu tries to hammer home the fact that patients are afforded vastly more protections than in the past. "There are a lot of committees and investigational review boards that keep track of clinical trials; things just don't happen anymore as they did in the past," she says. She also believes it helps if more providers of color communicate to patients.
Hsieh is very straightforward with his patients. He informs them about the HIV vector but assures them no one has ever tested positive for the virus as a result of its use.
Edwards notes that since many patients suffer psychosocial trauma as a result of their chronic pain, there already is some counseling infrastructure in place to help them cope. He believes such resources will have to be stretched further as a cure looms closer.
In the absence of formal mental health services, straight talk may be the best way to overcome wariness.
"If patients have misgivings, we try our best to address them, and let them know at the end of the day it is their decision to make," Hsieh says. "And even the patients who have gone through the gene therapy and it didn't work well -- they're still glad they took the chance."
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.”