Data sources for cost analysis of drug development R&D and clinical trials

Cost estimates for pre-clinical and clinical development across the pharmaceutical industry differ based on several factors. One of these is the source of data used by each costing study to inform these estimates. Several studies use private data, which can include confidential surveys filled out by pharmaceutical firms/clinical trial units and random samples from private databases^{3,9,10,14,15,16}. Other studies have based their cost estimates upon publicly available data, such as data from the FDA/national drug regulatory agencies, published peer-reviewed studies, and other online public databases^1,2,12,13,17.

Some have questioned the validity of using private surveys from large multinational pharmaceutical companies to inform cost estimates, saying that survey data may be artificially inflated by pharmaceutical companies to justify high therapeutic prices ^18,19,20. Another concern is that per trial spending by larger pharmaceutical companies and multinational firms would far exceed the spending of start-ups and smaller firms, meaning cost estimates made based on data from these larger companies would not be representative of smaller firms.

Failure rate of R&D and clinical trial pipelines

Many estimates include the cost of failures, which is especially the case for cost estimates “per approved drug”. As many compounds enter the clinical trial pipeline, the cost to develop one approved drug/compound includes cost of failures by considering the clinical trial success rate and cost of failed compounds. For example, if 100 compounds enter phase I trials, and 2 compounds are approved, the clinical cost per approved drug would include the amount spent on 50 compounds.

The rate of success used can massively impact cost estimates, where a low success rate or high failure rate will lead to much higher costs per approved drug. The overall probability of clinical success may vary by year and has been estimated at a range of values including 7.9%²¹, 11.83%¹⁰, and 13.8%²². There are concerns that some studies suggesting lower success rates have relied on small samples from industry curated databases and are thereby vulnerable to selection bias^12,22.

Success rates per phase transition also affects overall costs. When more ultimately unsuccessful compounds enter late clinical trial stages, the higher the costs are per approved compound. In addition, success rates are also dependent on therapeutic area and patient stratification by biomarkers, among other factors. For example, one study estimated the lowest success rate at 1.6% for oncological trials without biomarker use compared with a peak success rate of 85.7% for cardiovascular trials utilising biomarkers²². While aggregate success rates can be used to estimate costs, using specific success rates will be more accurate to estimate the cost of a specific upcoming trial, which could help with budgeting and funding decisions.

Out-of-pocket costs vs capitalised costs & interest rates

Cost estimates also differ due to reporting of out-of-pocket and capitalised costs. An out-of-pocket cost refers to the amount of money spent or expensed on the R&D of a therapeutic. This can include all aspects of setting up therapeutic development, from initial funding in drug discovery/device design, to staff and site costs during clinical trials, and regulatory approval expenses.

The capitalised cost of a new therapeutic refers to the addition of out-of-pocket costs to a yearly interest rate applied to the financial investments funding the development of a new drug. This interest rate, referred to as the discount rate, is determined by (and is typically greater than) the cost of capital for the relevant industry.

Discount rates for the pharmaceutical industry vary between sources and can dramatically alter estimates for capitalised cost, where a higher discount rate will increase capitalised cost. Most studies place the private cost of capital for the pharmaceutical industry to be 8% or higher^23,24, while the cost of capital for government is lower at around 3% to 7% for developed countries^23,25. Other sources have suggested rates from as high as 13% to as low as zero^13,23,26, where the zero cost of capital has been justified by the idea that pharmaceutical firms have no choice but to invest in R&D. However, the mathematical model used in many estimations for the cost of industry capital, the CAPM model, tends to give more conservative estimates²³. This would mean the 10.5% discount rate widely used in capitalised cost estimates may in fact result in underestimation.

While there is not a consensus on what discount rate to use, capitalised costs do represent the risks undertaken by research firms and investors. A good approach may be to present both out-of-pocket and capitalised estimated costs, in addition to rates used, justification for the rate used, and the estimates using alternative rates in a sensitivity analysis²⁶.

Costs variation over time

The increase in therapeutic development costs

Generally, there has been a significant increase in the estimated costs to develop a new therapeutic over time²⁶. One study reported an exponential increase of capitalised costs from the 1970s to the mid-2010s, where the total capitalised costs rose annually 8.5% above general inflation from 1990 to 2013¹⁰. Recent data has suggested that average development costs reached a peak in 2019 and had decreased the following two years⁹. This recent decrease in costs was associated with slightly reduced cycle times and an increased proportion of infectious disease research, likely in response to the rapid response needed for COVID-19.

Recent cost estimates

Costs can range with more than 100-fold differences for phase III/pivotal trials alone¹. One of the more widely cited studies on drug costs used confidential survey data from ten multinational pharmaceutical firms and a random sample from a database of publicly available data¹⁰. In 2013, this study estimated the total pre-approval cost at $2.6 billion USD per approved new compound. This was a capitalised cost, and the addition of post-approval R&D costs increased this estimate to $2.87 billion (2013 USD). The out-of-pocket cost per approved new compound was reported at $1.395 billion, of which $965 million were clinical costs and the remaining $430 million were pre-clinical.

Another estimate reported the average cost to develop an asset at $1.296 billion in 2013⁹. Furthermore, it reported that this cost had increased until 2019 at $2.431 billion and had since decreased to $2.376 billion in 2020 and $2.006 billion in 2021. While comparable to the previous out-of-pocket estimate for 2013, this study does not state whether their estimates are out-of-pocket or capitalised, making it difficult to meaningfully compare these estimates.

Publicly available data of 63 FDA-approved new biologics from 2009-2018 was used to estimate the capitalised (at 10.5%) R&D investment to bring a new drug to market at median of $985.3 million and a mean of $1.3359 billion (inflation adjusted to 2018 USD)¹². These data were mostly accessible from smaller firms, smaller trials, first-in-class drugs, and further specific areas. The variation in estimated cost was, through sensitivity analysis, mostly explained by success/failure rates, preclinical expenditures, and cost of capital.

Publicly available data of 10 companies with no other drugs on the market in 2017 was used to estimate out-of-pocket costs for the development of a single cancer drug. This was reported at a median of $648 million and a mean of $719.8 million¹³. Capitalised costs were also reported using a 7% discount rate, with a median of $754.4 million and mean of $969.4 million. By focusing on data from companies without other drugs on the market, these estimates may better represent the development costs per new molecular entity (NME) for start-ups as the cost of failure of other drugs in the pipeline were included while any costs related to supporting existing on-market drugs were systematically impossible to include.

One study estimated the clinical costs per approved non-orphan drug at $291 million (out-of-pocket) and $412 million (capitalised 10.5%)¹⁷. The capitalised cost estimate increased to $489 million when only considering non-orphan NMEs. The difference between these estimates for clinical costs and the previously mentioned estimates for total development costs puts into perspective the amount

spent on pre-clinical trials and early drug development, with one studynoting their pre-clinical estimates comprised 32% of out-of-pocket and 42% of capitalised costs¹⁰.

Things to consider about cost estimates

The issue with these estimates is that there are so many differing factors affecting each study. This complicates cost-based pricing discussions, especially when R&D cost estimates can differ orders of magnitude apart. The methodologies used to calculate out-of-pocket costs differ between studies^9,17, and the use of differing data sources (public data vs confidential surveys) seem to impact these estimates considerably.

There is also an issue with the transparency of data and methods from various sources in cost estimates. Some of this is a result of using confidential data, where some analyses are not available for public scrutiny⁸. This study in particular raised questions as estimates were stated without any information about the methodology or data used in the calculation of estimates. The use of confidential surveys of larger companies has also been criticised as the confidential data voluntarily submitted would have been submitted anonymously without independent verification¹².

Due to the limited amount of comprehensive and published cost data¹⁷, many estimates have no option but to rely on using a limited data set and making some assumptions to arrive at a reasonable estimate. This includes a lack of transparent available data for randomised control trials, where one study reported that only 18% of FDA-approved drugs had publicly available cost data¹⁸. Therefore, there is a need for transparent and replicable data in this field to allow for more plausible cost estimates to be made, which in turn could be used to support budget planning and help trial sustainability^18,26.

Despite the issues between studies, the findings within each study can be used to gather an idea of trends, cost drivers, and costs specific to company/drug types. For example, studies suggest an increasing overall cost of drug development from 1970 to peak in 2019¹⁰, with a subsequent decrease in 2020 and 2021⁹.

For a full list of references used in this article, please see the main report here: https://anatomisebiostats.com/biostatistics-blog/how-much-does-developing-a-novel-therapeutic-cost-factors-affecting-drug-development-costs-in-the-pharma-industry-a-mini-report/

Introduction

Data evaluating the costs associated with developing novel therapeutics within the pharmaceutical industry can be used to identify trends over time and can inform more accurate budgeting for future research projects. However, the cost to develop a drug therapeutic is difficult to accurately evaluate, resulting in varying estimates ranging from hundreds of millions to billions of US dollars between studies. The high cost of drug development is not purely because of clinical trial expenses. Drug discovery, pre-clinical trials, and commercialisation also need to be factored into estimates of drug development costs.

There are limitations in trying to accurately assess these costs. The sheer number of factors that affect estimated and real costs means that studies often take a more specific approach. For example, costs will differ between large multinational companies with multiple candidates in their pipeline and start-ups/SMEs developing their first pharmaceutical. Due to the amount and quality of available data, many studies work mostly with data from larger multinational pharmaceutical companies with multiple molecules in the pipeline. When taken out of context, the “$2.6 billion USD cost for getting a single drug to market” can seem daunting for SMEs. It is very important to clarify what scale these cost estimates represent, but cost data from large pharma companies are still relevant for SMEs as they can used to infer costs for different scales of therapeutic development.

This mini-report includes what drives clinical trial costs, methods to reduce these costs, and then explores what can be learned from varying cost estimates.

What drives clinical trial costs?

There is an ongoing effort to streamline the clinical trial process to be more cost and time efficient. Several studies report on cost drivers of clinical trials, which should be considered when designing and budgeting a trial. Some of these drivers are described below:

Study size

Trial costs rise exponentially with an increasing study size, which some studies have found to be the single largest driver in trial costs^1,2,3. There are several reasons for varying sample sizes between trials. For example, study size increases with trial phase progression as phases require different study sizes based on the number of patients needed to establish the safety and/or effectiveness of a treatment. Failure to recruit sufficient patients can result in trial delays which also increases costs⁴.

Trial site visits

A large study size is also correlated with a larger overall number of patient visits during a trial, which is associated with a significant increase in total trial costs^2,3. Trial clinic visits are necessary for patient screening, treatment and treatment assessment but include significant costs for staff, site hosting, equipment, treatment, and in some cases reimbursement for patient travel costs. The number of trial site visits per patient varies between trials where more visits may indicate longer and/or more intense treatment sessions. One estimate for the number of trial visits per person was a median of 11 in a phase III trial, with $2 million added to estimated trial costs for every +1 to the median².

Number & location of clinical trial sites

A higher number of clinical trial study sites has been associated with significant increase in total trial cost³. This is a result of increased site costs, as well as associated staffing and equipment costs. These will vary with the size of each site, where larger trials with more patients often use more sites or larger sites.

Due to the lower cost and shorter timelines of overseas clinical research^5,6, there has been a shift to the globalisation of trials, with only 43% of study sites in US FDA-approved pivotal trials being in North America⁷. In fact, 71% of these trials had sites in lower cost regions where median regional costs were 49%-97% of site costs in North America. Most patients in these trials were either in North America (39.7%), Western Europe (21%), or Central Europe (20.4%).

However, trials can face increased difficulties in managing and coordinating multiple sites across different regions, with concerns of adherence to the ethical and scientific regulations of the trial centre’s region^5,6. Some studies have reported that multiregional trials are associated with a significant increase in total trial costs, especially those with sites in emerging markets³. It is unclear if this reported increase is a result of lower site efficiency, multiregional management costs, or outsourcing being more common among larger trials.

Clinical Trial duration

Longer trial duration has been associated with a significant increase in total trial costs^3,4, where many studies have estimated the clinical period between 6-8 years^{8,9,10,11,12,13}. Longer trials are sometimes necessary, such as in evaluating the safety and efficacy of long-term drug use in the management of chronic and degenerative disease. Otherwise, delays to starting up a trial contribute to longer trials, where delays can consume budget and diminish the relevance of research⁴. Such delays may occur as a result of site complications or poor patient accrual.

Another aspect to consider is that the longer it takes to get a therapeutic to market (as impacted by longer trials), the longer the wait is before a return of investment is seen by both the research organisation and investors. The period from development to on-market, often referred to as cycle time, can drive costs per therapeutic as interest based on the industry’s cost of capital can be applied to investments.

Therapeutic area under investigation

The cost to develop a therapeutic is also dependent on the therapeutic area, where some areas such as oncology and cardiovascular treatments are more cost intensive compared with others^{1,2,5,6,12,14}. This is in part due to variation in treatment intensity, from low intensity treatments such as skin creams to high intensity treatments such as multiple infusions of high-cost anti-cancer drugs². An estimate for the highest mean cost for pivotal trials per therapeutic area was $157.2M in cardiovascular trials compared to $45.4M in oncology, and a lowest of $20.8M in endocrine, metabolic, and respiratory disease trials¹. This was compared to an overall median of $19M. Clinical

trial costs per therapeutic area also varied by clinical trial phase. For example, trials in pain and anaesthesia have been found to have the lowest average cost of a phase I study while having the highest average cost of a phase III study⁶.

It is important to note that some therapeutic areas will have far lower per patient costs when compared to others and are not always indicative of total trial costs. For example, infectious disease trials generally have larger sample sizes which will lead to relatively low per patient costs, whereas trials for rare disease treatment are often limited to smaller sample sizes with relatively high per patient costs. Despite this, trials for rare disease are estimated to have significantly lower drug to market costs.

Drug type being evaluated

As mentioned in the therapeutic areas section above, treatments may vary in intensity from skin creams to multiple rounds of treatment with several anti-cancer drugs. This can drive total trial costs due to additional manufacturing and the need for specially trained staff to administer treatments.

In the case of vaccine development, phase III/pivotal trials for vaccine efficacy can be very difficult to run unless there are ongoing epidemics for the targeted infectious disease. Therefore, some cost estimates of vaccine development include from the pre-clinical stages to the end of phase IIa, with the average cost for one approved vaccine estimated at $319-469 million USD in 2018¹⁵.

Study design & trial control type used

Phase III trial costs vary based on the type of control group used in the trial¹. Uncontrolled trials were the least expensive with an estimated mean of $13.5 million per trial. Placebo controlled trials had an estimated mean of $28.8 million, and trials with active drug comparators had an estimated mean cost of $48.9 million. This dramatic increase in costs is in part due to manufacturing and staffing to administer a placebo or active drug. In addition, drug-controlled trials require more patients compared to placebo-controlled, which also requires more patients than uncontrolled trials².

Reducing therapeutic development costs

Development costs can be reduced through several approaches. Many articles recommend improvements to operational efficiency and accrual, as well as deploying standardised trial management metrics⁴. This could include streamlining trial administration, hiring experienced trial staff, and ensuring ample patient recruitment to reduce delays in starting and carrying out a study.

Another way to reduce development costs can take place in the thorough planning of clinical trial design by a biostatistician, whether in-house or external. Statistics consulting throughout a trial can help to determine suitable early stopping conditions and the most appropriate sample size. Sample size calculation is particularly important as underestimation undermines experimental results, whereas overestimation leads to unnecessary costs. Statisticians can also be useful during the pre-clinical stage to audit R&D data to select the best available candidates, ensure accurate R&D data analysis, and avoid pursuing unsuccessful compounds.

Other ways to reduce development costs include the use of personalised medicine, clinical trial digitisation, and the integration of AI. Clinical trial digitisation would lead to the streamlining of clinical trial administration and would also allow for the integration of artificial intelligence into clinical trials. There have been many promising applications for AI in clinical trials, including the use of electronic health records to enhance the enrolment and monitoring of patients, and the potential use of AI in trial diagnostics. More information about this topic can be found in our blog “Emerging use-cases for AI in clinical trials”.

For more information on the methodology by which pharmaceutical development and clinical trials costs are estimated and what data has been used please see the article: https://anatomisebiostats.com/biostatistics-blog/estimating-the-costs-associated-with-novel-pharmaceutical-development-methods-and-limitations/

Cost breakdown in more detail: How is a clinical trial budget spent?

Clinical trial costs can be broken down and divided into several categories, such as staff and non-staff costs. In a sample of phase III studies, personnel costs were found to be the single largest component of trial costs, consisting of 37% of the total, whereas outsourcing costs made up 22%, grants and contracting costs at 21%, and other expenses at 21%³.

From a CRO’s perspective, there are many factors that are considered in the cost of a pivotal trial quotation, including regulatory affairs, site costs, management costs, the cost of statistics and medical writing, and pass-through costs²⁷. Another analysis of clinical trial cost factors determined clinical procedure costs made up 15-22% of the total budget, with administrative staff costs at 11-29%, site monitoring costs at 9-14%, site retention costs at 9-16%, and central laboratory costs at 4-12%^5,6. In a study of multinational trials, 66% of total estimated trial costs were spent on regional tasks, of which 53.3% was used in trial sites and the remainder on other management⁷.

Therapeutic areas and shifting trends

Therapeutic area had previously been mentioned as a cost driver of trials due to differences in sample sizes and/or treatment intensity. It is however worth mentioning that, in 2013, the largest number of US industry-sponsored clinical trials were in oncology (2,560/6,199 active clinical trials with 215,176/1,148,340 patients enrolled)^4,14. More recently, there has been a shift to infectious disease trials, in part due to the needed COVID-19 trials⁹.

Clinical trial phases

Due to the expanding sample size as a trial progresses, average costs per phase increase from phase I through III. Median costs per phase were estimated in 2016 at $3.4 million for phase I, $8.6 million for phase II, and $21.4 million for phase III³. Estimations of costs per patient were similarly most expensive in phase III at $42,000, followed by phase II at $40,000 and phase I at $38,500¹⁴. The combination of an increasing sample size and increasing per patient costs per phase leads to the drastic increase in phase costs with trial progression.

In addition, studies may have multiple phase III trials, meaning the median estimated cost of phase III trials per approved drug is higher than per trial costs ($48 million and $19 million respectively)². Multiple phase III trials can be used to better support marketing approval or can be used for therapeutics which seek approval for combination/adjuvant therapy.

There are fewer cost data analyses available on phase 0 and phase IV on clinical trials. Others report that average Phase IV costs are equivalent to Phase III but much more variable^5,6.

Orphan drugs

Drugs developed for the treatment of rare diseases are often referred to as orphan drugs. Orphan drugs have been estimated to have lower clinical costs per approved drug, where capitalised costs per non-orphan and orphan drugs were $412 million and $291 million respectively¹⁷. This is in part due to the limit to sample size imposed upon orphan drug trials by the rarity of the target disease and the higher success rate for each compound. However, orphan drug trials are often longer when compared to non-orphan drug trials, with an average study duration of 1417 days and 774 days respectively.

NMEs

New molecular entities (NMEs) are drugs which do not contain any previously approved active molecules. Both clinical and total costs of NMEs are estimated to be higher when compared to next in class drugs^13,17. NMEs are thought to be more expensive to develop due to the increased amount of pre-clinical research to determine the activity of a new molecule and the increased intensity of clinical research to prove safety/efficacy and reach approval.

Conclusion & take-aways

There is no one answer to the cost of drug or device development, as it varies considerably by several cost drivers including study size, therapeutic area, and trial duration. Estimates of total drug development costs per approved new compound have ranged from $754 million¹² to $2.6 billion¹⁰ USD over the past 10 years. These estimates do not only differ based on the data used, but also due to methodological differences between studies. The limited availability of comprehensive cost data for approved drugs also means that many studies rely on limited data sets and must make assumptions to arrive at a reasonable estimate.

There are still multiple practical ways that can be used to reduce study costs, including expert trial design planning by statisticians, implementation of biomarker-guided trials to reduce the risk of failure, AI integration and digitisation of trials, improving operational efficiency, improving accrual, and introducing standardised trial management metrics.

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