Clinical Trial Intelligence
How Long Do Phase I Oncology CTIS Reviews Take and What Factors Speed or Delay Approval?
Across 755 European Phase I oncology trials, the median interval from initial CTIS submission to first authorization was 86 days. Faster timelines clustered around selected submission months, single-country programs, orphan-designated trials and several common modality profiles; long delays were most consistently associated with broader country footprints, ADC or peptide/protein/enzyme programs, and late-calendar submissions.
Trial-level CTIS E2E
86d
median · SD 43.8
Authorized ≤90 days
52.3%
395 of 755 trials
Country Part II interval
262d
median · SD 269.2
Evidence base
755
trials · 1,870 Part II rows
Timeline definitions: E2E is one trial-level interval from initial CTIS submission to first authorization. Country analysis is limited to Part II and uses the recorded interval from earliest country Part II submission to latest decision or authorization. No E2E result is attributed to an individual country, and submission year is excluded from all factor analysis.
CTIS authorization timeline
How quickly did Phase I oncology trials reach first EU authorization?
The E2E median was 86 days, with an interquartile range of 34–112 days and SD of 43.8 days. The cumulative approval curve steepened between 90 and 120 days: 52.3% were authorized by day 90, rising to 85.4% by day 120.
Percentage completed within each interval
Phase I Oncology CTIS Review Times & Delay Factors · E2E: 755 trials · Part II: 1,870 country rowstrialagents.com
Conclusion
For EU submission planning, 90 days is only a median-adjacent milestone, not a high-confidence target. A 120-day planning envelope captured 85.4% of first authorizations, while 180 days captured 99.2%.
Country-specific CTIS Part II
Which countries had shorter or longer recorded Part II intervals?
Among countries with at least 10 usable records, Ireland had the shortest median at 45 days. Germany had the longest at 344 days. Standard deviations were large in nearly every major country, showing that country alone is not a reliable point estimate for an individual submission.
Median Part II days · countries with n≥10
Ireland
Median 45.0 · SD 182.4 · n=16
Austria
Median 154.0 · SD 193.5 · n=30
Netherlands
Median 187.0 · SD 254.8 · n=143
Portugal
Median 193.0 · SD 220.2 · n=19
Denmark
Median 202.0 · SD 288.0 · n=85
Norway
Median 247.0 · SD 256.6 · n=29
Poland
Median 255.5 · SD 241.0 · n=78
Sweden
Median 266.5 · SD 239.5 · n=42
Finland
Median 273.0 · SD 276.5 · n=14
France
Median 273.0 · SD 277.5 · n=335
Greece
Median 275.0 · SD 253.8 · n=29
Italy
Median 275.5 · SD 269.5 · n=228
Spain
Median 290.5 · SD 274.9 · n=428
Belgium
Median 302.0 · SD 278.0 · n=110
Czechia
Median 333.0 · SD 281.5 · n=32
Hungary
Median 343.5 · SD 292.9 · n=22
Germany
Median 344.0 · SD 269.4 · n=208
Low-volume countries — descriptive only
Croatia
7.0d median · SD — · n=1
Estonia
18.0d median · SD — · n=1
Slovenia
53.0d median · SD 36.8 · n=2
Slovakia
226.5d median · SD 126.1 · n=4
Bulgaria
237.5d median · SD 247.8 · n=4
Romania
314.0d median · SD 305.2 · n=9
Lithuania
365.0d median · SD — · n=1
Phase I Oncology CTIS Review Times & Delay Factors · Earliest Part II submission to latest country decision/authorizationtrialagents.com
Conclusion
Part II benchmarking should use country-specific ranges rather than a single EU-wide assumption. The high SDs and long upper tail also indicate that the extracted field can capture staged country additions or later decision events, so it should not be interpreted as the statutory initial assessment clock.
Submission timing
Did the month of initial CTIS submission matter?
February submissions were fastest at a 41-day median, followed by May and June at 43.5 and 44 days. November and December were slowest at 117.5 and 112 days; 71.0% of November submissions and 60.3% of December submissions took at least 90 days.
Initial CTIS submission month · no year variable used
January
92.0d · 54.8% ≥90d
February
41.0d · 17.9% ≥90d
August
96.0d · 53.7% ≥90d
September
60.0d · 39.5% ≥90d
October
75.5d · 47.8% ≥90d
November
117.5d · 71.0% ≥90d
December
112.0d · 60.3% ≥90d
Phase I Oncology CTIS Review Times & Delay Factors · Green ≤60d median · amber ≥100d mediantrialagents.com
Conclusion
The calendar-month pattern was one of the clearest observed timing signals. Where operationally feasible, avoiding late-year initial EU submissions may reduce timeline risk, but this remains an association rather than evidence that month itself causes delay.
Geographic and site complexity
Was country footprint more important than site count?
Single-country trials had a 68-day median, compared with 91–105.5 days across multi-country groups. Country count had a modest positive correlation with E2E time (Spearman ρ=0.19), while site count was much weaker (ρ=0.08).
Country footprint
1 country
68.0d
37.8% ≥90d · n=328
2–3 countries
105.5d
60.3% ≥90d · n=204
4–6 countries
91.0d
50.9% ≥90d · n=175
7+ countries
105.5d
56.2% ≥90d · n=48
Total site footprint
2–5 sites
88.0d
47.7% ≥90d
6–15 sites
89.0d
50.0% ≥90d
16–30 sites
86.0d
50.0% ≥90d
31+ sites
107.0d
55.9% ≥90d
Phase I Oncology CTIS Review Times & Delay Factors · Trial-level initial CTIS submission to first authorizationtrialagents.com
Conclusion
The main scale penalty appeared when moving from one country to a multi-country EU submission. Adding many sites inside the selected footprint contributed less than adding country-specific Part II packages and coordination layers.
Disease and modality
Which clinical profiles were associated with delay?
CNS and haematologic programs had lower descriptive medians than lung, breast and genitourinary programs. By modality, ADC and peptide/protein/enzyme trials had the highest medians and the largest shares exceeding 90 days.
Median days by disease group · n≥20
Haematologic
68.0d · n=151
Gastrointestinal
89.0d · n=77
Mixed / pan-tumour
91.0d · n=223
Genitourinary
104.0d · n=57
Phase I Oncology CTIS Review Times & Delay Factors · Disease categories derived from CTIS disease texttrialagents.com
Median days by modality presence · n≥20
Cell therapy
55.5d · 38.3% ≥90d
Small molecule
60.0d · 39.5% ≥90d
Monoclonal antibody
64.0d · 41.7% ≥90d
Radiopharmaceutical
74.0d · 42.1% ≥90d
Bispecific antibody
75.0d · 47.9% ≥90d
Peptide/protein/enzyme
107.0d · 68.9% ≥90d
Phase I Oncology CTIS Review Times & Delay Factors · Modalities are multi-label and not mutually exclusivetrialagents.com
Conclusion
Modality carried a stronger and more reproducible delay signal than disease category. ADC and peptide/protein/enzyme presence remained associated with 90-day delay after adjustment, whereas much of the disease-level variation weakened after accounting for program mix.
Design and operating model
Which design features separated faster and slower approvals?
Orphan-designated, paediatric, adaptive, dose-escalation and combination programs were faster descriptively. First-in-human trials were slower. CRO presence showed only a five-day median difference and was not a major independent timing signal.
Descriptive median and ≥90-day rate
Orphan-designated
53.0d
32.1% ≥90d · n=78
Non-orphan: 89d; 49.9% ≥90d
Paediatric
59.5d
41.2% ≥90d · n=80
Non-paediatric: 88d; 48.9% ≥90d
Adaptive design
69.0d
44.6% ≥90d · n=399
Non-adaptive: 92d; 51.9% ≥90d
Dose-escalation
73.0d
46.2% ≥90d · n=429
No escalation flag: 91d; 50.5% ≥90d
Combination treatment
69.0d
43.0% ≥90d · n=447
Non-combination: 96d; 55.4% ≥90d
First-in-human
94.0d
52.2% ≥90d · n=115
Not FIH: 71d; 44.4% ≥90d
Academic / hospital sponsor
55.0d
36.6% ≥90d · n=172
Industry: 93d; 52.2% ≥90d
CRO present
89.0d
50.0% ≥90d · n=284
No CRO: 84d; 46.9% ≥90d
Phase I Oncology CTIS Review Times & Delay Factors · Observed associations; categories overlaptrialagents.com
Conclusion
Several apparently faster design categories are likely markers of narrower geographies or different sponsor portfolios rather than intrinsic regulatory advantages. The more actionable finding is what did not strongly predict timing: endpoint counts, planned sample size, randomization and CRO presence added little standalone explanatory value.
Adjusted delay sensitivity
Which factors remained after simultaneous adjustment?
An exploratory logistic model for E2E delay of at least 90 days included submission month, country and site footprint, sample size, disease, modality, sponsor type, stage, paediatric and orphan status, adaptive and biomarker design, dose escalation, combination treatment, first-in-human status and CRO presence. Submission year was not included.
Adjusted odds ratios for ≥90-day E2E
Peptide / protein / enzyme
3.42×
higher odds of ≥90d
95% CI 1.62–7.23
ADC
2.09×
higher odds of ≥90d
95% CI 1.20–3.67
Country footprint
1.56×
per SD increase in log country count
95% CI 1.20–2.04
November submission
2.65×
higher odds vs April
95% CI 1.15–6.10
February submission
0.19×
odds vs April
95% CI 0.07–0.54
Orphan designation
0.49×
odds vs non-orphan
95% CI 0.26–0.90
Phase I Oncology CTIS Review Times & Delay Factors · Exploratory multivariable model · n=755 · no year variabletrialagents.com
Conclusion
Country footprint, ADC and peptide/protein/enzyme programs were the clearest independent risk signals. February submission and orphan designation remained protective, while November submission remained adverse. The model explained only a limited share of total variability, so these factors should inform risk buffers rather than deterministic forecasts.
Strategic Signal
What should EU Phase I oncology teams plan around?
120 days
A more reliable E2E planning envelope than 90 days, covering 85.4% of first authorizations.
+37.5d
Median difference between single-country and 2–3-country submissions.
2.1–3.4×
Adjusted ≥90-day delay odds for ADC and peptide/protein/enzyme programs.
No country E2E
Country benchmarking should remain Part II-specific; first authorization is a trial-level EU outcome.
Dataset basis: 755 unique European CTIS Phase I oncology trials with valid initial submission and first authorization dates; 2,066 trial-country records, of which 1,870 had a usable Part II processing-time value. All findings are observational and exploratory. No analysis was based on submission or authorization year.