Stanford Health Policy researchers, led by Josh Salomon, have been awarded a five-year grant from the Centers for Disease Control and Prevention (CDC) to conduct health and economic modeling to guide national and local policies and programs focusing on some of the most important infectious diseases in the United States.

The CDC grant establishes the Prevention Policy Modeling Lab at Stanford, continuing a multi-institution collaboration that began when Salomon was a professor at Harvard prior to joining Stanford in 2017.

“The overall mission of the Prevention Policy Modeling Lab is to leverage the best available evidence to inform strategic decision-making about major public health problems,” Salomon said. “We do this by combining techniques from decision science, simulation modeling and health economics to estimate and project major patterns and trends in these diseases and to evaluate different clinical and public health strategies to address them.”

The initiative will focus on policy and practice in the areas of tuberculosis, HIV, hepatitis, sexually transmitted infections and adolescent health. The grant from the Centers for Disease Control and Prevention supports a wide range of modeling activities, including those that assess: 

• Projections of future morbidity and mortality
• Burden and costs of diseases
• Costs and cost-effectiveness of interventions
• Population-level program impact
• Optimized resource allocation

Stanford researchers who are involved in the Modeling Lab include Douglas K. Owens, Margaret Brandeau, Eran Bendavid, Jeremy Goldhaber-Fiebert, Jason Andrews, Samuel So and Mehlika Toy. The consortium also includes partners at Harvard, Yale, Michigan, Boston University, Boston Medical Center and the MA Department of Public Health.

“As a multi-institution consortium, on any given problem we’re able to assemble a team that includes both subject matter experts and collaborators who specialize in statistics, epidemiology, data science, economics and decision analysis,” Salomon said. “The policy models that we develop allow us to synthesize a wide array of different types and sources of evidence to shed light on the essence of the problem and to weigh the likely benefits and costs of responding in different ways.”

Prior work from the consortium on the potential impact and cost-effectiveness of expanding testing for hepatitis C virus was cited in the recent decision by the U.S. Preventive Services Task Force to revise their screening recommendations to cover all adults. The Modeling Lab has also examined prospects and strategies for eliminaitng tuberculosis in the United States and policies relevant to the rising threat of antimicrobial-resistant gonococcal infection among other topics.

The United States has more people with new HIV diagnoses each year than any high-income nation. There is this widespread misconception out there that we’ve got it under control; that the drug cocktails are so effective that HIV is no longer a leading threat.

“Unfortunately, HIV remains a major public health problem in the U.S.,” said Stanford Health Policy’s Douglas K. Owens. He is chair of the U.S. Preventive Services Task Force, which issued two influential recommendations Tuesday for the prevention and treatment of HIV.

“Each year, almost 40,000 people acquire HIV, he said. “It’s not acceptable and requires our urgent attention.”

Owens, the Henry J. Kaiser, Jr., professor at Stanford Medicine, said an estimated 1.1 million people are currently living with HIV in this country — and more than 700,000 people have died of AIDS since the first cases were reported in 1981. Of the 38,281 new diagnoses of HIV reported in 2017, 81% were among men and 19% among women.

“There are highly effective preventive interventions that can help us toward the goal of ending the HIV epidemic in the U.S.,” said Owens, who is also an investigator at VA Palo Alto Health Care System “However, we know not enough people receive these interventions.”

The task force recommends clinicians screen everyone aged 15 to 65 and all pregnant women for HIV and offer pre-exposure prophylaxis (PrEP) — a pill that helps prevent HIV — to people at high risk of contracting the potentially fatal infection.

It released its recommendations with a series of articles and editorials in the Journal of the American Medical Association (JAMA), calling for dramatic action to end the AIDS epidemic in the United States once and for all. 

The task force is an independent, volunteer panel of national experts in prevention and evidence-based medicine who work to improve the health of all Americans by making recommendations. They typically give letter grades to its recommendations, and this time issued its highest grade, an A.

The draft recommendations were made last year and then put out for review and public comment. The recommendations made Tuesday are final.

The benefit of this endorsement could be substantial, according to one of the accompanying editorials in JAMA, because under the Affordable Care Act, Grade A and B recommendations made by the USPSTF should be covered by private insurance without patient cost-sharing.

“How this recommendation will be implemented is of critical importance because cost is a major barrier for people both to start and to stay on PrEP,” wrote Diane V. Havlir, MD, and Susan P. Buchbinder, MD, in their editorial. At present, they wrote, the average monthly retail cost for PrEP without insurance is nearly $2,000.

The task force members concluded “with high certainty” that while there are some small harms associated with PreP, the magnitude of benefit with oral tenofovir disoproxil fumarate-based therapy to reduce the risk of HIV infection in people at high risk is substantial.

“Clinicians can make a real difference toward reducing the burden of HIV in the United States, Owens said in the task force statement. “HIV screening and HIV prevention work to reduce new HIV infections and ultimately save lives.”

Fewer than half of all adults have ever been tested for HIV in the U.S. and many of those requiring more frequent testing are not receiving it. The task force emphasized that clinicians should make testing routine and ensure patients are given an environment that is free of judgment during discussions of sexual health.

Screening is the only way to know if a person has been infected with HIV because, after initial flu-like symptoms, HIV does not cause any signs of symptoms for several years. So the task force recommends HIV screening for everyone between of 15 and 65 and for pregnant women.

In addition to screening, people need to prevent getting HIV by using condoms during sex, the task force said, for those who inject drugs, using clean needles and syringes.

People at high risk for HIV have an additional strategy for prevention in taking PrEP, the task force said in its statement. “For people at high risk of getting HIV, the benefits of PrEP far outweigh the harms, which can include kidney problems and nausea.”

Read the full task force statement and accompanying articles and editorials in JAMA.  

U.S. government aid for treating children and adults with HIV and malaria in developing countries has done more than expand access to lifesaving interventions: It has changed how people around the world view the United States, according to a new study by researchers at the School of Medicine.

Compared with other types of foreign aid, investing in health is uniquely associated with a better opinion of the United States, improving its “soft power” and standing in the world, the study said.  

Favorability ratings of the United States increased in proportion to health aid from 2002 to 2016 and rose sharply after the implementation of the President’s Emergency Plan for AIDS Relief in 2003 and the launch of the President’s Malaria Initiative in 2005, the researchers report.

Their findings were published this week in the American Journal of Public Health. The lead author is postdoctoral scholar Aleksandra Jakubowski, PhD, MPH. The senior author is Eran Bendavid, MD, associate professor of medicine and a core faculty member at Stanford Health Policy.

“Using data on aid and opinions of the United States, we found that investments in health offer a unique opportunity to promote the perceptions of the United States abroad, in addition to disease burden relief,” the authors wrote. “Our study provides new evidence to support the notion that health diplomacy is a net win for the United States and recipient countries alike.”

The Trump administration, however, has proposed a 23% cut in foreign aid in its 2020 budget, including large reductions to programs that fight AIDS and malaria overseas.

The Stanford researchers believe their study is the first to add heft to the argument that U.S. health aid boosts the “soft power” that wins the hearts and minds of foreign friends and foes.

“Our study shows that investing in health aid improves our nation’s standing abroad, which could have important downstream diplomatic benefits to the United States,” Jakubowskisaid. “Investments in health aid help the United States accumulate soft power. Allowing the U.S. reputation to falter would be contrary to our own interests.” 

A Policy Debate

Many politicians and economists consider spending U.S. tax dollars on foreign aid as an ineffective, and possibly harmful, enterprise that goes unappreciated and leads to accusations of American meddling in other countries’ national affairs.

The U.S. government, for the past 15 years, has contributed more foreign health aid than any other country, significantly reducing disease burden, increasing life expectancy and improving employment in recipient countries, the authors wrote. Still, this generosity has historically constituted less than 1% of the U.S. gross domestic product.

“Our results suggest that the dollars invested in health aid offer good value for money,” the researchers wrote. “That is, the relatively low investment in health aid (in terms of GDP) has provided the United States with large returns in the form of improved public perceptions, which may advance the U.S. government’s ability to negotiate international policies that are aligned with American priorities and preferences.”

The researchers used 258 Global Attitudes Surveys, based on interviews with more than 260,000 respondents, conducted by the Pew Research Center in 45 low- to middle-income countries between 2002 and 2016.

Their analysis focused on the health sector, which includes several large programs for infectious disease control, but also support for nutrition, child health and reproductive health programs. They compared health aid to other major areas of U.S. investment: governance, infrastructure, humanitarian aid and military aid. They also constructed a database of news stories that mentioned the President’s Emergency Plan for AIDS Relief or the President’s Malaria Initiative by crawling through the online archives of the top three newspapers by circulation in each of the 45 countries.

They found that the probability of populations holding a very favorable opinion of the United States was 19 percentage points higher in the countries where and years when U.S. donations for health care were highest, compared with countries where and years when health aid donations were lowest. Using another metric, the researchers found that every additional $100 million in health aid was associated with a nearly 6 percentage-point increase in the probability of respondents indicating they had a “very favorable” opinion of the United States. 

In contrast, the researchers found, aid for governance, infrastructure, humanitarian and military purposes was not associated with a better opinion of the United States.

Bendavid, an infectious diseases physician and core faculty member of Stanford Health Policy, said that when he set out to conduct this research, he believed it would result “in a resounding thud” — that the “soft power” of health aid would have no impact on public opinion.

“For me, the notion that this program — hatched and headquartered in D.C. — would have impacts among millions in Nairobi and Dakar, seemed farfetched,” Bendavid said. “I was incredulous until all the pieces were in place.”

The ‘America First’ Agenda

The Trump administration’s “America First” agenda is calling for significant cuts to global health aid, particularly to the highly successful AIDS relief program, which was established by President George W. Bush. The administration’s budget, released in March, proposed a $860 million cut to the program; the President’s Malaria Initiative is facing a $331 million reduction in federal funding. That’s a decline of 18% and 44%, respectively.

The U.S. contribution to the Global Fund to Fight AIDS, Tuberculosis and Malaria would also decline by 17%, or $225 million, according to the Kaiser Family Foundation.

Yet beyond the reputational damage to the United States, such cuts could be a major setback to improving health outcomes in developing countries, the researchers said. After all, HIV knows no borders, and having more resilient health care systems is instrumental when facing public health crises, such as the Ebola outbreak in the Democratic Republic of Congo, Jakubowski said.

“The most direct impact of cutting the United States’ health aid allocations is the potential to undermine or reverse the progress that has been enabled by U.S. aid in curbing mortality and the spread of disease,” Bendavid said. “However, this study suggests there are also repercussions to the United States: the relationships the U.S. has built with recipient nations could also be undermined.”            

Other Stanford co-authors are Steven Asch, MD, MPH, professor of medicine, and former graduate student Don Mai.

Stanford’s Department of Medicine supported the work.

​

Fourteen years ago, Stanford Health Policy’s Douglas K. Owens and colleagues published a cost-effectiveness analysis that would change the face of HIV prevention. Their landmark study in The New England Journal of Medicine showed that expanding HIV screening would increase life expectancy and curb transmission of the disease — and was cost effective in virtually all health-care settings.

Not long after their model-based results were published, their findings became key evidence in the decision to expand screening by the Centers for Disease Control and Prevention. Their work has been used in HIV screening guidelines from the U.S. Preventive Services Task Force — which Owens now chairs — the American College of Physicians and the Department of Veterans Affairs, among others.

Owens and his Stanford colleague Margaret Brandeau, professor of management science and engineering, have led this team of decision scientists who have been at the forefront of developing scientific models for the screening and prevention of HIV for two decades now. This modeling team — which also includes colleagues from UCSF and Yale — has published nearly 250 peer-reviewed studies and is one of the most experienced and respected in the world.

But today, the opioid epidemic is threatening the hard-fought gains in the prevention and control of HIV and hepatitis C virus (HCV). In support of their continued work to address the opioid epidemic, Owens received a highly prestigious MERIT award from the National Institute on Drug Abuse (NIDA),which provides up to 10 years of funding for the team.

“We are extremely grateful to NIDA for this support and to our colleague at NIDA, Dr. Peter Hartsock, who has worked with us for over 20 years to mitigate the harms from HIV and HCV,” said Owens.

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The team will now turn its sights on the complex interplay of the opioid epidemic, and HIV and hepatitis C virus (HCV) transmission. The transmission of HCV has been fueled by the opioid epidemic, and HCV now kills more Americans than all other infectious diseases combined.  

“The unfolding opioid epidemic is a defining challenge for the public health and medical systems in the United States,” Owens, the principal investigator of the team, and his colleagues wrote in their grant proposal. “The reversal of life expectancy growth in the demographic groups most affected by the opioid epidemic represents the aggregation of a complex web of harmful public health and population trends, including a rise in overdoses, suicides, mental health afflictions, economic disadvantages, and infectious disease outbreaks.”

Indeed, for the first time since the 1960s, the U.S. life expectancy has contracted for the second year in a row; drug overdoses have been the leading cause of death for Americans under age 50, with an estimated two-thirds of those deaths resulting from opioids.

Since the last renewal of their NIDA-funding grant in 2013, the team has watched the dramatic rise of opioid overuse, injection drug use, and overdose become a national public health crisis, with more than 60,000 drug overdose deaths in the United States reported by the CDC.

“The growing use of needle-based opioids increases the likelihood of accelerating HIV and HCV transmission,” said co-investigator Jeremy Goldhaber-Fiebert, an associate professor of medicine and core faculty at Stanford Health Policy. “Identifying the best combination of approaches to reduce HIV and HCV transmissions stemming from the opioid epidemic is of critical public health importance.”

The other co-investigators on the team of the project, “Making Better Decisions: Policy Modeling for AIDS and Drug Abuse,” are:

1. Eran Bendavid, an infectious diseases physician and associate professor of medicine at Stanford who is another a seasoned HIV modeler and outcomes expert;
2. Keith Humphreys, professor of psychiatry and behavioral sciences at Stanford and a former senior policy advisor in the White House Office of National Drug Control Policy; 
3. David Paltiel, a Yale School of Public Health professor who pioneered policy options for mitigating the impact of HIV in the United States and abroad;
4. Gregg Gonsalves, an assistant professor of epidemiology at Yale and a 2018 MacArthur Foundation Fellow who will focus on developing new algorithms to detect and predict opioid-related outbreaks of HIV and HCV;
5. James Kahn of the Institute for Health Policy Studies at UCSF, professor of epidemiology and biostatistics and an expert on the individual and population impact of prevention and treatment for HIV, HCV and opioid use.

The End of AIDS? 

Toward 2012, a series of scientific advances led to calls for “the end of AIDS.” The two big factors were the cost of the “triple cocktail” of antiretrovirals plunging in developing countries and then huge donations from wealthy countries began pouring in to fight the disease.

Yet the researchers say successes have been too few and that the incidence of HIV remains far too high. About 40 million people were living with HIV around the world in 2017; an estimated 940,000 people died from AIDS-related illnesses that same year.

The year 2015 marked the first time in two decades that the number of HIV diagnoses tied to opioids increased.

"Although it was started by prescription opioid overprescribing, the epidemic has evolved to include significant injection opioid use which is now threatening to significantly increase the spread of infectious diseases like HIV and Hepatitis C,” said Humphreys.

The most visible example of an opioid-related HIV outbreak took place in Scott County, IN, in 2014-2015. A single infection introduced into the community resulted in nearly 200 new HIV cases within six months, largely related to oxymorphone injections. In 2017 and again in March 2018, two additional substantial outbreaks occurred in Scott County, likely linked to both risky sex and needle sharing. 

In addition, the CDC has identified 220 counties in 26 states that are uniquely vulnerable to HIV and HCV outbreaks related to opioid injections.

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“Developing models that forecast high-risk areas for HIV and HCV is essential for aligning surveillance and public health interventions with risk,” said Brandeau, a leader in designing models for the prevention of HIV and hepatitis, especially in drug abuse disorders.

There have also been striking increases in the injection of opioids and heroin that are closely linked to the spread of viral hepatitis. In the demographic areas most affected by opioids, the researchers found, diagnoses of acute hepatitis have more than quadrupled — reversing trends of the previous decade. And in the country as a whole, the number of new HCV cases has nearly tripled since 2010. 

“For any type of contact with an infected source such as a dirty needle, or even cocaine straws, HCV is by far the most rapidly transmissible of the blood-borne infections,” said Bendavid. “One of the challenging issues with hepatitis C is that its major health manifestations do not appear for many years after infection."

What’s the Plan? 

In the next five years, the team intends to evaluate how strategies to prevent and mitigate the harms of opioid use can decrease the spread of HIV and HCV and thereby reduce morbidity and mortality from opioid use. They have four specific goals: 

1. Model the effect of the opioid epidemic on transmission of HIV and HCV.
2. Model the epidemiological and population impacts of individual strategies to prevent and mitigate the harms of opioids and drug injection on HIV and HCV outcomes by evaluating prevention strategies;
3. Model the epidemiologic and population impact of portfoliosof strategies to mitigate the harms of opioid use and drug injection on HIV and HCV outcomes;
4. And model the impact of barriers to implementation of effective strategies to reduce the harms of opioid use on HIV and HCV.

“We will perform novel analyses assessing intervention impacts singly and in combination assessing outcomes for HIV, HCV and opioid use disorder,” the researchers wrote in their grant proposal.

Then, the researcher will model new methods for building complex multi-intervention and multi-disease models and developing adaptive testing algorithms for identifying outbreaks.

Finally, the team intends to assess the barriers and intervention approaches “that more realistically reflect implementation issues than current models and hence identify resource needs for system planning.”

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A national panel of medical experts is recommending for the first time that clinicians offer daily preventive medication to patients who are at high risk of acquiring HIV/AIDS.

The U.S. Preventive Services Task Force estimates that 1.1 million Americans are currently living with HIV. More than 700,000 people have died from AIDS in the United States since the first cases were reported in 1981 and some 40,000 Americans are diagnosed with the virus each year.

Though HIV is treatable, there is still no vaccine and it has significant health consequences.

But the Task Force said in a published draft recommendation on Tuesday that it found “convincing evidence” that taking a daily pre-exposure prophylaxis, known as PrEP, provides a substantial benefit in decreasing the risk of HIV infection in people at high risk. 

PrEP is a combination of two drugs, tenofovir disoproxil fumarate and emtricitabine, taken in one daily pill. The Centers for Disease Control and Prevention says that PrEP reduces the risk of getting HIV from sex by more than 90 percent and by 70 percent for intravenous drug users.

“Unfortunately, HIV is still a major problem in the United States,” said Stanford Health Policy’s Douglas K. Owens, vice-chairman of the Task Force, an independent, voluntary panel of experts in prevention and evidence-based medicine. “But the evidence on this daily treatment is that, if you take it properly, it’s very effective.”

The Task Force, whose recommendations are followed by primary care physicians and clinical practices across the country, gave the recommendation its highest grade, an A. But it noted that PrEP currently is not being used in many persons at high risk of HIV infection. 

“We hope our recommendation will bring attention to a very effective preventative service,” Owens said. “We want clinicians to be aware that for patients at high risk of HIV, PrEP is an important preventive strategy to discuss.”

The global AIDS epidemic has slowed in recent year. AIDS-related deaths have been reduced by more than 50 percent since the peak of the AIDS crisis in 2004. In 2017, 940,000 people died from AIDS-related illnesses worldwide, compared to 1.4 million in 2010 and 1.9 million in 2004.

But many people remain at risk, including sex workers and people who have been trafficked.

The Task Force recommendation is only for those Americans who remain at high risk for contracting the virus, including:

1. Sexually active men whose male partners are already living with HIV, or have a recent sexually transmitted infection (STI) such as syphilis, gonorrhea, or chlamydia;
2. Heterosexual women and men who are sexually active and have an STI or partner living with HIV or who are inconsistent in their use of condoms with a partner at high risk of HIV;
3. People who inject drugs and either share drug injection equipment.

The Task Force reaffirmed its 2013 recommendation that people ages 15 to 65 and all pregnant women also be screened for HIV in an additional draft recommendation. Both recommendations are open for public comment until December 26.

A key concern weighing heavily on those attending this week’s global conference on AIDS is the diminishing donor support to fight the communicable disease, which has claimed an estimated 35 million lives since the beginning of the epidemic.

“That’s on everybody’s mind now — how to continue facing the epidemic with the shrinking resources,” said Eran Bendavid, a core faculty member at Stanford Health Policy and assistant professor at Stanford Medicine attending the conference in Durban, South Africa.

Donor government funding to support HIV efforts in low- and middle-income countries fell for the first time in 2015, decreasing from $8.6 billion in 2014 to $7.5 billion last year, according to a new report by the Kaiser Family Foundation and UNAIDS.

Funding for HIV treatment declined for 13 of 14 major donor governments, with the U.S. continuing to provide more donor funding for HIV than any other country or organization.

“There’s a sense of panic about how we’re going to fill the shortfall in funding,” Bendavid said. “All the major donors are here, PEPFAR, the Global Fund, and everyone is saying `We need more to continue the fight.’

“But, in my mind,” Bendavid continued, “the conversation that is mostly missing is the one between the organizations on the front lines and the national ministries of health and finance. See what they can do to get domestic resources to fill the gap.”

PEPFAR — the President’s Emergency Plan for AIDS Release — is the U.S. government initiative to help those suffering from HIV/AIDS.

Bendavid, an infectious disease physician, joins 18,000 global leaders, researchers, activists and front-line health workers attending the conference July 18-22.

The U.N. General Assembly last month pledged to end the AIDS epidemic by 2030. But more than half of the nearly 37 million people around the world infected with HIV still have no access to the antiretroviral therapy that is saving so many lives.

U.S. Secretary-General Ban Ki-moon said on the opening day of AIDS2016 that when the conference was last held in Durban 16 years ago, less than 1 percent of all people living with HIV in developing countries had access to treatment.

“Today, the world has proven that when we come together, we can transform lives,” Ban said, noting that of the 36.7 million people living with HIV today, about 46 percent of infected adults have access to antiretroviral treatment.

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“In addition, medicines are more effective and less toxic, technology allows diagnosis in 20 minutes or less, generic medicines reduced the cost of treatment to just a dollar a day and great international finance has been made available,” Ban said.

Still, the secretary-general warned, “the gains are inadequate — and fragile,” when you consider that more than half of all people living with HIV still lack access to treatment.

Bendavid, who spoke by telephone from Durban, gave a symposium at the conference on Tuesday that summarizes his research and provides his conclusions on the most effective approaches to use donor resources.

He said the while the global burden of noncommunicable diseases, such as heart disease and cancer, is greater than HIV, malaria, or TB, the interventions available to combat infectious diseases are more cost-effective. 

“Basically, the resource constraints are forcing us to think carefully about what to invest in, and we want to invest in what works,” Bendavid said, adding that donor funding typically goes straight to the disease rather than the local health system infrastructure.

“The scarce donor resources should not be directed towards interventions that are either inefficacious or costly,” he argued. “The opportunity cost of investing in costly or ineffective interventions is very high when you consider the millions who could benefit from inexpensive, simple interventions such as bed nets and drugs for TB.”

He conceded that he typically gets push back on this line of reasoning.

“But when you’re talking about what you can do with very limited resources, investing in noncommunicable diseases, in my mind, jeopardizes the premise of donor funding: There are many people who would be happy to shut down PEPFAR and the Global Fund if they were shown to be ineffective.”

He published a paper earlier this year that found the U.S. government has invested $1.4 billion in HIV prevention programs that promote sexual abstinence and marital fidelity. But there is no evidence that the programs have been effective at changing sexual behavior and reducing HIV Risk.

Bendavid said his presentation at the symposium was received with a mix of understanding and concern.

“People mentioned that funding health systems could have averted Ebola, and that the fight against HIV needs to address health systems,” he said. “I agree, but also think governments should step up and help fill some of those gaps.”

The U.S. government has invested $1.4 billion in HIV prevention programs that promote sexual abstinence and marital fidelity, but there is no evidence that these programs have been effective at changing sexual behavior and reducing HIV risk, according to a new Stanford University School of Medicine study.

Previously: PEPFAR has saved lives – and not just from HIV/AIDS, Stanford study finds
 

People who inject drugs make up less than 1 percent of the U.S. adult population. But about 10 percent of new HIV infections in this country are attributable to injection drug use.

So it stands to reason that focusing on HIV interventions for drug users who get high through injection could have tremendous public health benefits, Stanford researchers contend in a study published in the Annals of Internal Medicine.

“We already know that the health benefits of interventions for high-risk individuals extend to the entire U.S. population,” said Cora Bernard, a PhD student in Management Science and Engineering at Stanford University and lead author of the paper, “Cost-Effectiveness of HIV Preexposure Prophylaxis for People Who Inject Drugs in the United States.”

“And with the recent surges in opiate drug use in the U.S. and HIV outbreaks in places like Scott County, Indiana, it’s increasingly important to invest in prevention programs that are both effective and cost-effective, ” Bernard said.

The authors used new clinical data to determine that pre-exposure HIV prophylaxis, combined with frequent screening and prompt treatment for those who do become infected, could reduce the HIV burden among those who inject drugs.

And that provides a public health benefit for all Americans.

”Value is an important consideration in health policy decisions that have substantial budget implications,” said Jeremy Goldhaber-Fiebert, an associate professor of medicine at Stanford and senior author of the paper.

However, prescription drugs costs in the United States are among the highest in the world, making this form of intervention quite expensive.

The U.S. Food and Drug Administration approved a daily combination of 300 mg of tenofovir disoproxil fumarate (TDF) and 200 mg of emtricitabine (FTC) for HIV-negative patients, at a cost of about $10,000 per patient a year.

Add to that the cost of the HIV screening and assessment for adverse effects every three months and monitoring for toxicities every six months.

“This kind of cost scales fast,” said Bernard. “Although you’d be preventing the downstream costs of some infections, providing PrEP to 25 percent of HIV-negative people who inject drugs for just one year would require an upfront investment of over $3 billion.”

“Our analysis highlights the importance of trying to provide this effective intervention less expensively,” noted Douglas K. Owens, MD, MS, of the VA Palo Alto Health Care System, and professor of medicine at Stanford. 

Successful Trials

Many trials have shown that daily oral pre-exposure prophylaxis (PrEP) — or taking HIV medications to reduce the chance of infection — can prevent heterosexual and same-sex transmission of HIV.

The Bangkok Tenofovir Study, the first randomized trial of PrEP for people who inject drugs, reported a 49 percent reduction in HIV infection in this high-risk population in Thailand.

The Centers for Disease Control and Prevention (CDC) revised its clinical practice guidelines in 2014 to recommend that PrEP be considered for any adult who injected drugs within the previous six months, shared needles, enrolled in drug dependence treatment, or was at increased risk for sexual transmission.

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Although prior studies have explored the cost-effectiveness of PrEP for men who have sex with men, people who inject drugs differ in risk behaviors and HIV incidence. So the authors performed a model-based evaluation of the cost-effectiveness of expanding PrEP for people who inject drugs in the United States.

They incorporated new clinical trial results with epidemiologic and economic data to determine the optimal conditions under which pre-exposure interventions can be delivered to this high-risk population.

Their model captures sexual and injection transmissions between people who inject drugs, gay men, and all other U.S. adult heterosexuals between 2015 and 2035. The model includes opioid agonist therapy, such as methadone treatment, HIV screening and awareness, and antiretroviral treatment.

The authors found that PrEP along with frequent HIV screening and antiretroviral drugs for those who do become infected averted 26,700 infections and reduced HIV prevalence among people who inject drugs by 14 percent, compared to the current status quo. Achieving these benefits costs $253,000 per quality-adjusted life year (known as QALY, a common metric used to compare cost-effectiveness interventions.)

In comparison, needle-syringe exchange programs cost in the range of $4,500 to $34,000 per quality-adjusted life year.

Total expenditures for a PrEP program for this high-risk population could be as much as $44 billion over 20 years. This is equivalent to annually spending around 10 percent of the current federal budget for domestic HIV/AIDS on PrEP for people who inject drugs.

Is it worth it?

The authors concluded that frequent screening and pre-exposure prophylaxis, as well as prompt treatment for those who become infected, could reduce the HIV burden among people who inject drugs and provide substantial public health benefits.

They determined that enrolling 25 percent of HIV-negative people who inject drugs in a program that combined PrEP, screening and antiretroviral drugs would reduce the HIV burden in the United States.

But it is expensive.

“Cost effectiveness is only one of many considerations for policymakers, who must also evaluate the ethical dimensions of an HIV prevention program for a population with generally low access to health services,” the authors wrote.

However, given that there are other interventions for this population with demonstrated cost-effectiveness, they conclude that policymakers will want to consider the broad range of programs available for HIV prevention in this group.

The authors are now at work to directly compare PrEP with other prevention programs and identify cost-effective strategies for this high-risk population.

In an editorial that accompanies the paper, Rochelle P. Walensky, MD, MPH, a professor of medicine at Harvard Medical School, asks: “What good is preventing HIV if we do not first save that life at HIV risk?”

“As biomedical advances finally hold the promise of both effective HIV prevention and durable virologic suppression,” Walensky continues, “it may seem heretical to disfavor investments in PrEP for PWID. But now is the time to be maximally efficient (dare we say even frugal?) with HIV prevention resources to ensure their greatest impact, because the problems related to PWID (such as the immediate and high mortality associated with overdose) are far greater than the no-longer-deadly threat of HIV itself.”