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. Author manuscript; available in PMC: 2025 Sep 20.
Published in final edited form as: Clin Pharmacol Ther. 2024 Dec 10;117(5):1264–1271. doi: 10.1002/cpt.3512

Mapping the Clinical Development Trajectory of Cell and Gene Therapy Products

Magdi Elsallab 1,2, Michelle Ouvina 3, Andrea Arfe 4, Florence T Bourgeois 1,3,5
PMCID: PMC12447590  NIHMSID: NIHMS2108480  PMID: 39655466

Abstract

While cell and gene therapies (CGTs) have emerged as promising modalities to treat conditions with limited therapeutic options, their unconventional development is fraught with uncertainty, rendering them high-risk assets for many pharmaceutical companies. Here, we assess the clinical development trajectories of CGT products by estimating probabilities of successful clinical trial phase transitions and the likelihood of achieving regulatory approval. We included all CGT products entering clinical development from 1993 to 2023 and intended for marketing in the United States, Europe, Japan, Canada, and Switzerland. Associations between product success and characteristics were investigated. In sub-analyses, we examined the clinical trajectories of two promising product types, chimeric antigen receptor T (CAR T) cell therapies and adeno-associated viral (AAV) vector-based gene therapies. We identified 995 CGT products corresponding to 1,961 development programs. A total of 44 CGTs secured at least one regulatory approval, corresponding to an overall likelihood of approval of 5.3% (95% CI 4.0–6.9). Development programs with an orphan designation had a higher likelihood of approval than those without (9.4%, 95% CI 6.6–13.3 vs. 3.2%, 95% CI 2.0–4.9), while programs for oncology indications had a lower likelihood of approval compared to those for non-oncology indications (3.2%, 95% CI 1.6–5.1 vs. 8.0%, 95% CI 5.7–11.1). CAR T cells and AAV gene therapies had a similar overall likelihood of approval of 13.6% (95% CI 7.3, 23.9) and 13.6% (95% CI 6.4, 26.7), respectively. In conclusion, CGT products have a low overall likelihood of approval with variability based on orphan status, therapeutic area, and product type.

Cell and Gene therapy (CGT) products are diverse biologics that promise to cure conditions with high disease severity and limited therapeutic options. As of December 2023, the U.S. Food and Drug Administration (FDA) had approved 26 CGT products and is projecting the approval of 10–20 CGT products annually by 2025. The cumulative number of FDA-approved CGTs is estimated to reach 64 products by 2030.1,2 Nonetheless, CGT product development remains challenging and requires substantial research investment with a high degree of uncertainty.3,4 For instance, in contrast to small molecules or other biologics, CGT products require substantial investment and innovation in advanced manufacturing technologies.5,6 Furthermore, variability in long-term response to CGT products creates uncertainty around drug pricing and reimbursement, exposing developers to additional risks.7–9 An improved understanding of the development trajectories and success rates of these products across trial phases could inform strategic development approaches and support ongoing innovation and investment in the field.

One of the pivotal metrics in guiding pharmaceutical development strategies is the likelihood of product progression through successive stages of development and the overall likelihood of approval.2,10,11 While several comprehensive studies have characterized the probabilities of success for drug development for certain indications and product types, there is limited information on the success rates of CGT products despite their unique challenges.12–16 In this study, we assess the clinical development trajectories of CGT products by estimating probabilities of successful clinical trial phase transitions and the likelihood of achieving regulatory approval. We focus on products initiating clinical development from 1993 to 2023 and intended for approval in the United States, the European Union, Japan, Canada, and Switzerland. We examine the association between product characteristics and the probabilities of success and perform sub-analyses focused on chimeric antigen receptor T (CAR T) cells and adeno-associated viral (AAV) vector-based gene therapies.

METHODS

Data source

Data on CGT products were obtained from AdisInsight, a proprietary database that identifies and tracks commercial pharmaceutical products through the development process.17 The database has been used in a number of analyses to characterize clinical development and regulatory milestones for a variety of product types.18–22

Selection of study cohort

We identified all CGT products entering clinical development from the inception of the database to May 31, 2023. Gene therapies were defined as products that achieve their effect by transcription or translation of transferred genetic material or by altering host genetic sequences. We further categorized gene therapies as ex vivo or in vivo therapies. Ex vivo gene therapies are those that introduce genetic material into cells outside of the body, followed by infusion of these cells into patients, as is the case with CAR T cell therapies for hematological malignancies. In vivo gene therapies require a vector to deliver genetic material to the desired cells inside the body, such as AAV vector-based gene therapies for Leber congenital amaurosis. Cell therapies, on the contrary, are autologous, allogeneic, or xenogeneic cells that have been manipulated or processed ex vivo before introduction into the body. These manipulations include cell propagation, expansion, selection, or pharmacological treatment, as in mesenchymal stem cell therapy for the treatment of fistulas in patients with Crohn’s disease.

A CGT was eligible for analysis if it was studied in at least one clinical trial conducted in one of the core countries of the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH). These countries consist of the founding members (United States, European Union countries, and Japan) and the standing members (Canada and Switzerland) of the ICH. For each CGT product, we retrieved all clinical trials from AdisInsight that studied the product for any indication. Products were excluded if all clinical trials for a product were missing start dates or information on the trial phase. Information on the product characteristics, including orphan status, disease area, and the use of regulatory expedited pathways, was extracted from the database for each product. CAR T cell products, as well as AAV based gene therapies were identified through manual screening of all included products.

Identification and classification of development programs Development programs were defined as the sequence of clinical trials studying a product for an indication or group of closely related indications sharing the same High-Level Group Term (HLGT) in the Medical Dictionary for Regulatory Activities (MedDRA) (Figure S1). CGT products could be associated with more than one development program. Basket trials testing products for multiple indications in the same study were considered separate development programs when indications were not in the same HLGT. Therapeutic areas were assigned for each drug using the MedDRA classification. Development programs could attain one of three statuses: market approval, stalled development, or development in progress (Figure S2).14 Development programs were defined as stalled if all trials were discontinued or if the development did not progress from one clinical trial phase to the next after a given follow-up period. Trial discontinuation was based on final trial statuses of “terminated,” “suspended,” or “discontinued” without the presence of other ongoing clinical trials. Failure to progress was defined as the lack of new trial activity from the end date of the latest trial to 360, 540, or 730 days for trial phases I, II, and III, respectively. For products with a regulatory submission, failure to progress was defined as a lack of marketing approval 360 days after regulatory submission. Data were censored on May 31, 2023, with development programs that did not result in product approval or that did not meet the definition for stalled development as of this date considered still in progress.

Measures of product development success

The probability of phase success was defined as the proportion of development programs that advanced from one trial phase to the next. The overall likelihood of approval for a CGT product was estimated across all development programs as well as for the lead development programs. Lead programs were defined as those that advanced to the most advanced trial phase. For example, if a product had separate programs reaching Phase II and Phase III trials, the Phase III program was considered the lead program. We further estimated the likelihood of approval by the product’s biological category (ex vivo gene therapy, in vivo gene therapy, and cell therapy), target indication (oncology vs. non-oncology), orphan designation, and use of expedited regulatory programs. In the United States, these included fast-track, regenerative medicine advanced therapy (RMAT) and breakthrough therapy designation, and in the E.U., PRIority MEdicines (PRIME) designation.

The cumulative probability of success from the start of clinical development to approval was estimated for lead development programs. Similarly, we estimated the cumulative probability of stalling.

Data analysis

To estimate the probability of success, we used a modified approach based on prior analyses to impute any missing trials in the database.14 Specifically, we implemented an additional regulatory submission stage in the development pathway to account for the transition from phase III to regulatory submission and from regulatory submission to approval. We adjusted the statistical model accordingly. In brief, to estimate the probability of success, we assumed that all development programs followed an idealized drug development process, starting with phase I and progressing through phase II, phase III, and regulatory submission. This allowed for the use of an imputation method to account for any trial phases not captured in the database due to missing trials. For instance, if trials for a drug candidate were observed in phase I and phase III, then the transition from phase I to phase II and from phase II to phase III was imputed. Multiple trials could be conducted in each phase, and phase success was defined as the presence of at least one trial in the next phase.12–14 Missing clinical trial end dates (n = 181) were imputed using the median duration of trials that shared the same trial phase and status.14

For the purpose of the analysis, phase I/II trials were considered as phase I and phase II/III as phase III.18 The phase success and likelihood of approval were calculated using methods described in prior studies.12–14 Based on prior analyses, the probability of success in phase i, denoted as P(i), was estimated by considering the proportion of development programs that advanced to the next phase, denoted as P(i + 1), among the development programs that concluded P(i) (i.e., excluding development programs still in progress in P(i)).12–14 By extension, the overall likelihood of approval was calculated as the proportion of development programs that secured marketing approval in at least one ICH country among all development programs, excluding programs determined to be in progress. For each probability calculation, confidence intervals were estimated using Wilson score intervals.23

To estimate the cumulative probability of success or stalling, drug development programs were followed for up to 20 years from the time of entry in clinical development until approval or stalling.24 To account for competing risk (i.e., development programs that reach approval cannot also be stalled), we used Kalbfleisch-Prentice cumulative probability estimates.24–27

Data were analyzed using R statistical software (version 4.2.0).28 Tidyverse package was used for data wrangling, imputation, and probability estimation.29 Competing risk probabilities were estimated using the Cmprsk package.30 Cumulative risk plots were generated using the survminer package.31 All other visualizations were created using GraphPad Prism (version 10.0.2) and BioRender.

RESULTS

Characteristics of cell and gene therapy development

We identified 1,796 CGT products, of which 995 met inclusion criteria (Figure S3). These products corresponded to 1,961 development programs (mean of 2.0 development programs per product), with similar distributions across the three product categories (Table 1). There were 320 (32.1%) products with at least one orphan designation. Of the FDA-based expedited regulatory programs, fast-track designation was the most common, with 158 (15.9%) receiving this designation. PRIME designation was granted by the European Medicines Agency (EMA) to 42 (4.2%) products. By far, the most common disease area studied was oncology, with 499 (42.3%) products and 1,201 (61.2%) development programs. The majority of the oncology products were ex-vivo gene therapies (614/1,202, 51.1%) (Table S1). The next most common disease areas studied were nervous system disorders (N = 81, 6.9%) and infectious diseases (N = 76, 6.4%). Most of the products for these categories were cell therapies, with 53 of 98 (54%) programs for nervous system disorders and 47 of 76 (62%) programs for infectious diseases studying cell therapies (Table S1). The number of development programs entering the clinical stage increased over time with an annual growth rate of 27.8% (95% CI 6.4, 49.1) (Figure S4).

Table 1.

Characteristics of cell and gene therapy products and development programs

Cell and gene therapy products, N (%) Development programs, N (%)
(n = 995) (n = 1961)
Cell and gene therapy product categories
Ex vivo gene therapy 345 (35) 696 (35)
In vivo gene therapy 319 (32) 567 (29)
Cell therapy 331 (33) 698 (36)
Orphan designation 320 (32) 627 (32)
Expedited regulatory programs
Fast track (FDA) 158 (16) 309 (16)
Regenerative Medicine Advanced Therapy designation (FDA) 69 (7) 160 (8)
Breakthrough therapy designation (FDA) 31 (3) 93 (5)
PRIME designation (EMA) 42 (4) 84 (4)
Disease areasa
Oncology 499 (42) 1201 (61)
Nervous system disorders 81 (7) 98 (5)
Infectious diseases 76 (6) 77 (4)
Metabolism and nutrition disorders 74 (6) 74 (4)
Eye disorders 59 (5) 69 (4)
Musculoskeletal and connective tissue disorders 46 (4) 68 (4)
Cardiac disorders 45 (4) 56 (3)
Blood and lymphatic system disorders 51 (4) 55 (3)
Immune system disorders 42 (4) 43 (2)
Skin and subcutaneous tissue disorders 40 (3) 45 (2)
Vascular disorders 36 (3) 39 (2)
Endocrine disorders 35 (3) 36 (2)
Gastrointestinal disorders 19 (2) 21 (1)
Renal and urinary disorders 16 (1) 16 (1)
Respiratory disorders 16 (1) 16 (1)
Reproductive system and breast disorders 10 (1) 12 (1)
Other 34 (3) 35 (2)
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EMA, European Medicines Agency; FDA, Food and Drug Administration; PRIME, PRIority MEdicine. aCell and gene therapy products developed for multiple disease areas (n = 347) were included in all relevant groups.

Probability of phase success and likelihood of approval

CGT products were studied in a total of 2,783 clinical trials. For all development programs, the probability of successful transition from phase I to II was 53.3% (95% CI 50.4, 56.2), from phase II to III, 48.4% (95% CI 43.7, 53.1), and from phase III to regulatory submission, 45.7% (95% CI 37.6, 54.0) (Figure 1; Figure S5; Table S2). The highest probability of success was for the transition from regulatory submission to approval, at 81.0% (95% CI 69.1, 89.1). This corresponded to an overall likelihood of approval of 5.3% (95% CI 4.0, 6.9). Probabilities were consistently slightly higher for each phase transition when considering lead development programs, with a significantly higher overall likelihood of approval of 9.8% (95% CI 7.4, 13.0).

Figure 1.

Figure 1.

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Successful phase transition and likelihood of approval for cell and gene therapies. (a) All development programs (n = 1961) and lead development programs (n = 995). (b) Phase transition and likelihood of approval for ex vivo gene therapy (n = 696), in vivo gene therapy (n = 567), and cell therapy (n = 698). App, approval; Sub, submission.

The overall likelihood of approval across the three CGT product categories was similar, ranging from 4.4% (95% CI 2.4, 7.6) for in vivo gene therapies to 5.9% (95% CI 3.6, 9.7) for ex vivo gene therapies (Figure 1). However, there was variation in the probability of success between categories for certain phase transitions. Ex vivo gene therapies had a significantly lower probability of phase I to II transition at 38.5% (95% CI 33.2, 44.2) compared to in vivo gene therapies at 55.6% (95% CI 50.3, 60.7) and cell therapies at 60.3% (95% CI 56.0, 64.4). However, they exhibited the highest rate of successful transition from regulatory submission to approval at 100% (95% CI 79.6, 100.0), compared to 78.6% (95% CI 52.4, 92.4) and 73.3% (95% CI 55.5, 85.8) for ex vivo and in vivo gene therapies, respectively.

Overall, 44 CGT products, corresponding to 47 development programs, secured marketing approvals in at least one of the ICH core countries as of May 31, 2023. Approved products included 13 (29.5%) ex vivo gene therapies, 11 (25.0%) in vivo gene therapies, and 20 (45.5%) cell therapies. The most common therapeutic area was oncology (n = 14, 31.8%), followed by musculoskeletal disorders (n = 6, 13.6%) and skin and subcutaneous tissue disorders (n = 4, 9.1%) (Table S3).

The cumulative probability of achieving approval within 10 years of starting clinical development was 4.4% (95% CI 2.8, 6.6), and within 20 years, 10.1% (95% CI 6.9, 14.1) (Figure S6; Table S4). Conversely, the cumulative probability of a development program stalling within 10 years was 43.0% (95% CI 38.4, 47.4), and within 20 years, 73.5% (95% CI 65.8, 79.6).

Probabilities of success based on cell and gene therapy product characteristics

We identified 320 products with at least one orphan designation, corresponding to 627 development programs (Table 1). These programs had a likelihood of approval of 9.4% (95% CI 6.6, 13.3), which was significantly higher compared to products without orphan designations (3.2%, [95% CI 2.0, 4.9]) (Figure 2). Development programs for oncology indications had a lower likelihood of approval at 3.2% (95% CI 1.6, 5.1) compared to those for non-oncology indications at 8.0% (95% CI 5.7, 11.1) (Figure 2). This was largely the result of lower success in phase I to II transitions (42.5% [95% CI 38.7, 46.4] vs. 66.0% [95% CI 61.9, 69.9]) and phase II to III (37.7% [95% CI 30.6, 45.3] vs. 54.8% [95% CI 48.8, 60.6]). Finally, we found differences based on the use of expedited regulatory programs. Development programs for products with fast-track designations had the lowest likelihood of approval at 1.4% (95% CI 0.4, 5.0), while programs for products with breakthrough designation had the highest likelihood of approval at 34.0% (95% CI 22.4–47.9). The EMA’s PRIME designation was associated with a similarly high likelihood of approval at 43.2% (95% CI 28.7, 59.1) (Table S2).

Figure 2.

Figure 2.

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Cell and gene therapy product characteristics and likelihood of approval. (a) Successful phase transition and likelihood of approval based on orphan designation status (orphan programs = 627, non-orphan programs = 1334). (b) Successful phase transition and likelihood of approval based on oncology target indication (oncology programs = 1201, non-oncology programs = 760). App, approval; Sub, submission.

Probabilities of success for CAR T products and AAV gene therapies

There were 168 CAR T cell products studied in 293 development programs and 148 AAV gene therapies tested in 163 development programs. The two product types had similar trajectories in terms of transitions across phases, with some nonsignificant differences (Figure 3). AAV based gene products had a higher probability of phase I to II transition compared to CAR T cell products (62.2% [95% CI 50.8, 72.4] vs. 40.9% [95% CI 31.2, 51.4], respectively). However, CAR T-cell products had a higher probability of phase III to BLA transition (90.0% [95% CI 59.6, 98.2] vs. 80.0% [95% CI 49.0, 94.3]) as well as transition from BLA to approval (100% [95% CI 70.9, 100.0] vs. 85.7% [95% CI 48.7, 97.4]). The overall likelihood of approval for CAR T cell products was 13.6% (95% CI 7.3, 23.9). Similarly, AAV based gene therapies had an overall likelihood of approval of 13.6% (95% CI 6.4, 26.7). Overall, 7 CAR T cell products, corresponding to 9 development programs, achieved at least one approval, while 6 AAV based gene therapies, corresponding to 6 development programs, were approved in at least one of the ICH core countries.

Figure 3.

Figure 3.

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Development of CAR T products and AAV gene therapies. (a) Successful phase transition and likelihood of approval for CAR T product development programs (n = 293). (b) Successful phase transition and likelihood of approvals for AAV gene therapies (n = 163). App, approval; Sub, submission.

DISCUSSION

Among 995 CGT products entering clinical development from 1993 to 2023, the overall likelihood of product approval was 5.3%. The lowest probability of successful transition was for phase III trials to regulatory submission, while the highest was for submission to product approval, which reached 81.0%. The likelihood of approval was similar across CGT product categories but higher for products with an orphan designation and lower for those indicated for oncologic conditions.

Most prior studies examining drug development programs have focused on success rates across drug classes and therapeutic domains without focusing on a specific drug class. An early report by Hay et al.13 assessed 7,300 development programs across all drugs studied from 2003 to 2011 and reported a likelihood of approval of 10.4%. In their updated analysis of 9,704 development programs initiated from 2011 to 2020, the likelihood of approval decreased slightly to 7.9%.16 In another analysis by Wong et al.14 that utilized a similar methodology to ours and also spanned all drug classes and therapeutic areas and focused on development activity from 2000 to 2015, the likelihood of approval was reported at 13.8% for all indications and 21.6% for lead indications across 41,040 development programs. Our findings demonstrate a lower success rate for CGT products for both all indications and lead indications. A contributing factor may be the high proportion of therapies for oncology indications, which comprised 61% of development programs in our sample. Products targeting oncologic conditions have been shown to have a lower likelihood of approval compared to drugs in other therapeutic areas. Thomas et al. reported a likelihood of approval of 5.3% among oncology development programs, while Wong et al. reported a likelihood of approval of 3.4%.14,16 These results are comparable to our findings of 3.2% among development programs for oncology indications, indicating that the success rate for CGT products may not be substantially different from other drug classes. Stratified analyses of CGT product categories revealed differences in success rates across stages of clinical development. Ex vivo gene therapies had the lowest rate of transition from phase I to II, which may be attributable to the higher rate of acute adverse reactions (e.g., cytokine release syndrome) compared to in vivo gene therapies and cell therapies.32 During later development phases, we observed a reversal, with ex vivo products demonstrating a higher rate of success, including marketing approval for all products with a regulatory submission. Cell therapies, on the contrary, demonstrated high early rates of success but progressively lower probability of phase transition, with the lowest rate of regulatory submission approval. This may be related to the more favorable safety profile of these products, which benefits early development, but the lower overall efficacy, which emerges during later clinical development.33 For example, MesoBlast, a stem cell therapy for graft vs. host disease, was denied FDA marketing approval multiple times from 2020 to 2023 on the grounds of lack of meaningful reduction in inflammation.34 Similarly, NurOwn, a stem cell therapy for the treatment of amyotrophic lateral sclerosis, was denied FDA approval in 2023 due to limited efficacy in the phase III trial.35

Expedited regulatory programs granted by the FDA and EMA were associated with variable likelihoods of product approval. While the fast-track program was the most used program, it was associated with the lowest overall rate of approval. Fast-track designation does not require clinical data to demonstrate safety or efficacy, with a fairly high rate of designation approval at 70%.36 The RMAT program, which was associated with a higher likelihood of product approval, was established to support the development of regenerative therapies and requires clinical evidence for approval. Only 40% of applicants received the RMAT designation from 2016 to 2022.37 The highest likelihoods of product approval were observed with the FDA’s breakthrough therapy designation and the EMA’s PRIME designation. For both these programs, the level of evidence needed to secure the designation is more substantial compared to fast track and RMAT, and both are granted at lower rates (33% from 2013 to 2022 and 25% from 2016 to 2021, respectively).36–39 While we were not able to determine whether the higher success seen for products in certain programs was attributable to the program itself or related to the selection of more promising drug candidates, this would be an important question for regulatory agencies to consider as they assess the purpose and impact of these programs.

Both CAR T-cell products and AAV based gene therapies had a high likelihood of approval. Similar to the ex vivo gene therapies, there was a low probability of successful transition from phase I to II for CAR T-cell therapies, which improved in later phases. AAV gene therapies experienced generally high probabilities of successful phase transition, with slightly lower success in the BLA submission phase. The analysis by Thomas et al. also explored the likelihood of approval of complex biologics such as CAR T cells.16 In their analysis, the overall probability of approval for 67 CAR T-cell therapies entering development from 2011 to 2020 was 17.3%, slightly higher than our estimate of 13.6%. The difference could be related to the different study periods, the different and larger set of products analyzed in the current study (n = 168), or the use of products as opposed to development programs as the unit of analysis. The emerging success of CAR T-cell products and AAV based gene therapies may be related to the focused research and development approach and the academic-industry partnership around these products. Many of the approved CAR T-cell products and AAV gene therapies for monogenetic diseases were initiated in the academic environment and later licensed to industry.40 Another factor is the focus of these products on rare indications, which, as shown in our analysis, were associated with a higher probability of success. Our analysis has several limitations. Phase I/II trials had to be recategorized as phase I, which could have led to an underestimation of phase I success and an overestimation of phase II success. However, categorizing phase I/II trials as phase II would have inflated the phase I success rate. Therefore, our categorization is more conservative, limiting the number of imputations performed by the algorithm. Information on other expedited programs (i.e., FDA’s accelerated approval and priority review) was only available for approved products and, therefore, could not be assessed. Lastly, the accuracy of the estimated probabilities relies on the completeness of data provided by AdisInsight on CGT product development programs. However, given the widespread requirement for trial registration by regulatory authorities, it is unlikely that development programs were systematically missed.18,41–43

Our findings offer valuable insights that can support innovation in the CGT landscape. With the first wave of CGT products showing success, we are witnessing a second wave of increased investment in CGT products, evidenced by the substantial rise in new development programs, particularly since 2015. The lower overall likelihood of approval for CGTs compared to conventional drugs highlights the unique hurdles in translating cutting-edge science into clinical success, particularly for oncology-focused therapies. However, the emerging pockets of success exemplified by CAR T-cell and AAV based therapies underscore the need for focused, precision-driven approaches that can overcome these translational barriers. Advancements in the pre-clinical phase, aimed at better understanding the mechanisms of action, could further refine the products entering clinical trials. Moreover, the nuanced performance of orphan products and the expedited programs, such as RMAT and breakthrough therapy designations, suggest opportunities to further refine these pathways. By optimizing regulatory support to address the specific challenges of CGT development, agencies could facilitate progression accross clinical phases and expedite availability of transformative therapies for patient care.

Supplementary Material

1

Study Highlights.

WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?

Several studies have characterized the probabilities of success for drug development programs for certain indications and product types. However, there is limited information on the clinical development trajectories of cell and gene therapy (CGT) products despite their unique challenges.

WHAT QUESTION DID THIS STUDY ADDRESS?

What is the probability of successful transitions across trial phases for CGTs, and what is the overall likelihood of approval for these products?

WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?

The overall likelihood of approval for CGTs was low at 5.3%, with substantial variation based on product characteristics. Specifically, products with orphan designations had a higher probability of success compared to non-orphan products, while products targeting oncology indications had a lower probability of success compared to those in other therapeutic areas. Certain specific products, such as CAR T cell therapies and AAV based gene therapies, showed a higher probability of success.

HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?

This study provides a comprehensive analysis of development trajectories for CGTs spanning the past two decades, including CAR T cell therapies and AAV based gene therapies. We anticipate that these findings can help inform regulators, manufacturers, and other stakeholders to ensure ongoing innovation and investment in the field and to increase efficiencies and success rates in the development of these products.

Footnotes

CONFLICT OF INTEREST

The authors declared no competing interests for this work.

BIBLIOGRAPHY

Associated Data

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Supplementary Materials

1
NIHMS2108480-supplement-1.pdf (1.4MB, pdf)

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