Guidance for Industry 

 
S9 Nonclinical Evaluation 

for 

Anticancer Pharmaceuticals 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
U.S. Department of Health and Human Services 

Food and Drug Administration 

Center for Drug Evaluation and Research (CDER) 

Center for Biologics Evaluation and Research (CBER) 

 
March 2010 

ICH 

 
   
Guidance for Industry 

 
 
S9 Nonclinical Evaluation 

for 

Anticancer Pharmaceuticals 

 
 
 
 
Additional copies are available from: 

 
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Division of  Drug Information, WO51, Room  2201 
 
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http://www.fda.gov/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/default.htm  

 
 
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 Food and Drug  Administration 

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http://www.fda.gov/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInformation/Guidances/default.htm 
 
 
 
 
U.S. Department of Health and Human Services 

Food and Drug Administration 

Center for Drug Evaluation and Research (CDER) 

Center for Biologics Evaluation and Research (CBER) 

 
March 2010 

ICH 

 
  
   
TABLE OF CONTENTS 

 
 
I.   INTRODUCTION (1, 1.1)................................................................................................ 1 
 
A.   Background (1.2)............................................................................................................................1
  
B.   Scope (1.3).......................................................................................................................................2
  
C.   General Principles (1.4).................................................................................................................3
  
II.   STUDIES TO SUPPORT NONCLINICAL EVALUATION (2) ................................. 3 
 
A.   Pharmacology (2.1) ........................................................................................................................3
  
B.   Safety Pharmacology (2.2).............................................................................................................3
  
C   Pharmacokinetics (2.3)..................................................................................................................4
  
D.   General Toxicology (2.4) ...............................................................................................................4
  
E.   Reproduction Toxicology (2.5)......................................................................................................4
  
F.   Genotoxicity (2.6) ...........................................................................................................................5
  
G.   Carcinogenicity (2.7)......................................................................................................................5
  
H.   Immunotoxicity (2.8)......................................................................................................................5
  
I.   Photosafety testing (2.9).................................................................................................................5
  
III. 	  NONCLINICAL DATA TO SUPPORT CLINICAL TRIAL DESIGN AND 

MARKETING (3) ............................................................................................................. 6 
 
A.   Start Dose for First Administration in Humans (3.1).................................................................6 
 
B. 	  Dose Escalation and the Highest Dose in a Clinical Trial (3.2)..................................................6
  
C. 	  Duration and Schedule of Toxicology Studies to Support Initial Clinical Trials (3.3)............6
  
D. 	  Duration of Toxicology Studies to Support Continued Clinical Development  

  and Marketing (3.4) .......................................................................................................................7
  
E. 	  Combination of Pharmaceuticals (3.5).........................................................................................7
  
F.	   Nonclinical Studies to Support Trials in Pediatric Populations (3.6)........................................7
  
IV. 	  OTHER CONSIDERATIONS (4)................................................................................... 8 
 
A.   Conjugated Products (4.1).............................................................................................................8
  
B.   Liposomal Products (4.2)...............................................................................................................8
  
C.   Evaluation of Drug Metabolites (4.3)...........................................................................................8
  
D.   Evaluation of Impurities (4.4).......................................................................................................8
  
V.   NOTES (5) ......................................................................................................................... 9 
 
 
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1
 
Guidance for Industry  
 
S9 Nonclinical Evaluation for Anticancer Pharmaceuticals  

 
 
 
This guidance represents the Food and Drug Administration's (FDA's) current thinking on this topic.  It 
does not create or confer any rights for or on any  person and does not operate to bind FDA or the public.  
You can use an alternative approach if the approach satisfies the requirements of the applicable statutes 
and regulations.  If you want to discuss an alternative approach, contact the FDA staff responsible for 
implementing this guidance.  If you cannot identify the appropriate FDA staff, call the appropriate 
number listed on the title page of this guidance.  
 
 
 
 
 
 
I.  INTRODUCTION (1, 1.1) 
 
The purpose of this guidance is to provide information to assist in the design of an appropriate 
program of nonclinical studies for the development of anticancer pharmaceuticals.  The guidance 
provides recommendations for nonclinical evaluations to support the development of anticancer 
pharmaceuticals in clinical trials for the treatment of patients with advanced disease and limited 
therapeutic options. 
This guidance aims to facilitate and accelerate the development of anticancer pharmaceuticals 
and to protect patients from unnecessary adverse effects, while avoiding unnecessary use of 
animals, in accordance with the 3R principles (reduce/refine/replace), and other resources. 
As appropriate, the principles described in other ICH guidances should be considered in the 
development of anticancer pharmaceuticals.  Specific situations where recommendations for 
nonclinical testing deviate from other guidance are described in this document. 
A.  Background (1.2) 
 
                                                 
1  This  guidance was developed within the Expert  Working Group (Safety) of the International Conference on  
Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) and has been  
subject to consultation  by the regulatory parties, in accordance with the ICH process.  This guidance has been 
endorsed by the ICH Steering Committee at Step 4  of the ICH process, October  2009.  At  Step 4  of the process, the 
final draft is recommended for adoption to the regulatory bodies of the European  Union, Japan, and the United  
States. 
   
Because malignant tumors are life-threatening, the death rate from these diseases is high, and 
existing therapies have limited effectiveness, it is desirable to provide new, effective anticancer 
drugs to patients more expeditiously. 
There have been no internationally accepted objectives or recommendations on the design and 
conduct of nonclinical studies to support the development of anticancer pharmaceuticals in 
clinical trials for the treatment of patients with advanced disease and limited therapeutic options.  
Nonclinical evaluations are conducted to: 
(1) identify the pharmacologic properties of a pharmaceutical,  
(2) establish a safe initial dose level for the first human exposure, and  
(3) understand the toxicological profile of a pharmaceutical (e.g., identification of target 
organs, exposure-response relationships, and reversibility). 
In the development of anticancer drugs, clinical studies often involve cancer patients whose 
disease condition is progressive and fatal.  In addition, the dose levels in these clinical studies 
often are close to or at the adverse effect dose levels.  For these reasons, the type, timing, and 
flexibility called for in the design of nonclinical studies of anticancer pharmaceuticals can differ 
from those elements in nonclinical studies for other pharmaceuticals.  
B.  Scope (1.3) 
 
This guidance provides information for pharmaceuticals that are intended to treat cancer in 
patients with serious and life threatening malignancies.  For the purpose of this guidance, this 
patient population is referred to as patients with advanced cancer. The guidance applies to both 
small molecule and biotechnology-derived pharmaceuticals (biopharmaceuticals), regardless of 
the route of administration.  This guidance describes the type and timing of nonclinical studies in 
relation to the development of anticancer pharmaceuticals in patients with advanced cancer and 
references other guidance as appropriate.  It describes the minimal considerations for initial 
clinical trials in patients with advanced cancer whose disease is refractory or resistant to 
available therapy, or where current therapy is not considered to be providing benefit.  The 
nonclinical data to support Phase 1 and the clinical Phase 1 data would normally be sufficient for 
moving to Phase 2 and into second or first line therapy in patients with advanced cancer.  The 
guidance also describes further nonclinical data to be collected during continued clinical 
development in patients with advanced cancer.  When an anticancer pharmaceutical is further 
investigated in cancer patient populations with long expected survival (e.g., those administered 
pharmaceuticals on a chronic basis to reduce the risk of recurrence of cancer), the 
recommendations for and timing of additional nonclinical studies depend upon the available 
nonclinical and clinical data and the nature of the toxicities observed. 
 
This guidance does not apply to pharmaceuticals intended for cancer prevention, treatment of 
symptoms or side effects of chemotherapeutics, studies in healthy volunteers, vaccines, or 
cellular or gene therapy. If healthy volunteers are included in clinical trials, the ICH M3 
guidance should be followed.  Radiopharmaceuticals are not covered in this guidance, but some  
of the principles could be adapted. 
 
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C.  General Principles (1.4) 
 
The development of each new pharmaceutical calls for studies designed to characterize its 
pharmacological and toxicological properties according to its intended use in humans.  
Modification of standard nonclinical testing protocols generally is warranted to address novel 
characteristics associated with the pharmaceutical or with the manner in which it is to be used in 
humans. 
The manufacturing process can change during the course of development.  However, the active 
pharmaceutical substance used in nonclinical studies should be well characterized and should 
adequately represent the active substance to be used in the clinical trials. 
In general, nonclinical safety studies that are used to support the development of a 
pharmaceutical should be conducted in accordance with Good Laboratory Practices. 
 
II.  STUDIES TO SUPPORT NONCLINICAL EVALUATION (2) 
 
A.  Pharmacology (2.1) 
 
Prior to Phase 1 studies, preliminary characterization of the mechanism(s) of action and schedule 
dependencies, as well as anti-tumor activity of the pharmaceutical, should have been made.  
Appropriate models should be selected based on the target and mechanism of action, but the 
pharmaceutical need not be studied using the same tumor types intended for clinical evaluation.  
These studies can: 
 	  provide nonclinical proof of principle; 
 	  guide schedules and dose-escalation schemes; 
 	  provide information for selection of test species; 
 	  aid in start dose selection and selection of investigational biomarkers, where appropriate; 
and, 
 	  if relevant, justify pharmaceutical combinations.  
Understanding the secondary pharmacodynamic properties of a pharmaceutical could contribute 
to the assessment of safety for humans, and those properties might be investigated as appropriate. 
B.  Safety Pharmacology (2.2) 
 
An assessment of the pharmaceuticals effect on vital organ functions (including cardiovascular, 
respiratory, and central nervous systems) should be available before the initiation of clinical 
studies; such parameters could be included in general toxicology studies.  Detailed clinical 
observations following dosing and appropriate electrocardiographic measurements in nonrodents 
are generally considered sufficient. Conducting stand-alone safety pharmacology studies to 
support studies in patients with advanced cancer is not called for.  In cases where specific 
concerns have been identified that could put patients at significant additional risks in clinical 
trials, appropriate safety pharmacology studies described in ICH S7A and/or S7B should be 
 
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considered. In the absence of a specific risk, such studies will not be called for to support 
clinical trials or for marketing. 
 
C  Pharmacokinetics (2.3) 
 
The evaluation of limited pharmacokinetic parameters (e.g., peak plasma/serum levels, area 
under the curve (AUC), and half-life) in the animal species used for nonclinical studies can 
facilitate dose selection, schedule, and escalation during Phase 1 studies.  Further information on 
absorption, distribution, metabolism, and excretion of the pharmaceutical in animals should 
normally be generated in parallel with clinical development.  
D.  General Toxicology (2.4) 
 
The primary objective of Phase 1 clinical trials in patients with advanced cancer is to assess the 
safety of the pharmaceutical.  Phase 1 assessments can include dosing to a maximum tolerated 
dose (MTD) and dose limiting toxicity (DLT).  Toxicology studies to determine a no observed 
adverse effect level (NOAEL) or no effect level (NOEL) are not considered essential to support 
clinical use of an anticancer pharmaceutical.  As  the toxicity of the pharmaceutical can be greatly 
influenced by its schedule of administration, an approximation of its clinical schedule should be 
evaluated in toxicology studies.  This is further discussed in sections III.C and III.D (3.3 and 
3.4). 
Assessment of the potential to recover from toxicity should be provided to understand whether 
serious adverse effects are reversible or irreversible.  A study that includes a terminal nondosing 
period is called for if there is severe toxicity at approximate clinical exposure and recovery 
cannot be predicted by scientific assessment.  This scientific assessment can include the extent 
and severity of the pathologic lesion and the regenerative capacity of the organ system showing 
the effect. If a study of recovery is called for, it should be available to support clinical 
development.  The demonstration of complete recovery is not considered essential.   
For small molecules, the general toxicology testing usually includes rodents and nonrodents.  In 
certain circumstances, determined case-by-case, alternative approaches can be appropriate (e.g., 
for genotoxic drugs targeting rapidly dividing cells, a repeat-dose toxicity study in one rodent 
species might be considered sufficient, provided the rodent is a relevant species).  For 
biopharmaceuticals, see ICH S6 for the number of species to be studied. 
Toxicokinetic evaluation should be conducted as appropriate. 
E.  Reproduction Toxicology (2.5) 
 
An embryofetal toxicology assessment is conducted to communicate potential risk for the 
developing embryo or fetus to patients who are or might become pregnant.  Embryofetal toxicity 
studies of anticancer pharmaceuticals should be available when the marketing application is 
submitted, but these studies are not considered essential to support clinical trials intended for the 
treatment of patients with advanced cancer.  These studies are also not considered essential for 
the purpose of marketing applications for pharmaceuticals that are genotoxic and target rapidly 
dividing cells (e.g., crypt cells, bone marrow) in general toxicity studies or belong to a class that 
has been well characterized as causing developmental toxicity. 
 
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For small molecules, embryofetal toxicology studies are typically conducted in two species as 
described by ICH S5(R2). In cases where an embryofetal developmental toxicity study is 
positive for embryofetal lethality or teratogenicity, a confirmatory study in a second species is 
usually not warranted. 
 
For biopharmaceuticals, an assessment in one pharmacologically relevant species should usually 
be sufficient.  This assessment might be done by evaluating the toxicity during the period of 
organogenesis or study designs as described by ICH S6.  Alternative approaches might be 
considered appropriate if scientifically justified.  The alternative approaches might include a 
literature assessment, assessment of placental transfer, the direct or indirect effects of the 
biopharmaceutical, or other factors. 
 
A study of fertility and early embryonic development is not warranted to support clinical trials or 
for marketing of pharmaceuticals intended for the treatment of patients with advanced cancer.  
Information available from general toxicology studies on the pharmaceuticals effect on  
reproductive organs should be used as the basis of the assessment of impairment of fertility. 
A pre- and postnatal toxicology study is generally not warranted to support clinical trials or for 
marketing of pharmaceuticals for the treatment of patients with advanced cancer.  
F.  Genotoxicity (2.6) 
 
Genotoxicity studies are not considered essential to support clinical trials for therapeutics 
intended to treat patients with advanced cancer.  Genotoxicity studies should be performed to 
support marketing (see ICH S2).  The principles outlined in ICH S6 should be followed for 
biopharmaceuticals.  If the in vitro assays are positive, an in vivo assay might not be warranted. 
 
G.  Carcinogenicity (2.7) 
 
The appropriateness of a carcinogenicity assessment for anticancer pharmaceuticals is described 
in ICH S1A. Carcinogenicity studies are not warranted to support marketing for therapeutics 
intended to treat patients with advanced cancer.  
  
H.  Immunotoxicity (2.8) 
 
For most anticancer pharmaceuticals, the design components of the general toxicology studies 
are considered sufficient to evaluate immunotoxic potential and support marketing.  For 
immunomodulatory pharmaceuticals, additional endpoints (such as immunophenotyping by flow 
cytometry) might be included in the study design. 
 
I.   Photosafety testing (2.9) 
 
An initial assessment of phototoxic potential should be conducted prior to Phase 1, based on 
photochemical properties of the drug and information on other members in the class.  If  
assessment of these data indicates a potential risk, appropriate protective measures should be 
taken during outpatient trials. If the photosafety risk cannot be adequately evaluated based on 
 
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nonclinical data or clinical experience, a photosafety assessment consistent with the principles 
described in ICH M3 should be provided prior to marketing. 
 
 
III. 	 NONCLINICAL DATA TO SUPPORT CLINICAL TRIAL DESIGN AND 
MARKETING (3) 
 
A. 	 Start Dose for First Administration in Humans (3.1) 
 
The goal of selecting the start dose is to identify a dose that is expected to have pharmacologic 
effects and is reasonably safe to use.  The start dose should be scientifically justified using all 
available nonclinical data (e.g., pharmacokinetics, pharmacodynamics, toxicity), and its selection 
based on various approaches (see Note 2). For most systemically administered small molecules, 
interspecies scaling of the animal doses to an equivalent human dose is usually based on 
normalization to body surface area.  For both small molecules and biopharmaceuticals, 
interspecies scaling based on body weight, AUC, or other exposure parameters might be 
appropriate. 
 
For biopharmaceuticals with immune agonistic properties, selection of the start dose using a 
minimally anticipated biologic effect level (MABEL) should be considered. 
B. 	 Dose Escalation and the Highest Dose in a Clinical Trial (3.2) 
 
In general, the highest dose or exposure tested in the nonclinical studies does not limit the dose-
escalation or highest dose investigated in a clinical trial in patients with cancer.  When a steep 
dose- or exposure-response curve for severe toxicity is observed in nonclinical toxicology 
studies, or when no preceding marker of severe toxicity is available, smaller than usual dose 
increments (fractional increments rather than dose doubling) should be considered.   
C. 	 Duration and Schedule of Toxicology Studies to Support Initial Clinical 
Trials (3.3)  
 
In Phase 1 clinical trials, treatment can continue according to the patients response, and in this 
case, a new toxicology study is not called for to support continued treatment beyond the duration 
of the completed toxicology studies.   
The design of nonclinical studies should be appropriately chosen to accommodate different 
dosing schedules that might be utilized in initial clinical trials.  It is not expected that the exact 
clinical schedule always will be followed in the toxicological study, but the information provided 
from the toxicity studies should be sufficient to support the clinical dose and schedule and to 
identify potential toxicity. For example, one factor that can be considered is the half-life in the 
test species and the projected (or known) half-life in humans. Other factors could include 
exposure assessment, toxicity profile, saturation of receptors, etc. Table 1 provides examples of 
nonclinical treatment schedules that are commonly used in anticancer pharmaceutical 
development and can be used for small molecules or biopharmaceuticals. In cases where the 
available toxicology information does not support a change in clinical schedules, an additional 
toxicology study in a single species is usually sufficient. 
 
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D. 	 Duration of Toxicology Studies to Support Continued Clinical Development 
and Marketing (3.4) 
 
The nonclinical data to support Phase 1 and the clinical Phase 1 data would normally be 
sufficient for moving to Phase 2 and into second or first line therapy in patients with advanced 
cancer. In support of continued development of an anticancer pharmaceutical for patients with 
advanced cancer, results from repeat dose studies of 3 months duration following the intended 
clinical schedule should be provided prior to initiating Phase 3 studies.  For most 
pharmaceuticals intended for the treatment of patients with advanced cancer, nonclinical studies 
of 3 months duration are considered sufficient to support marketing.   
When considering a change in the clinical schedule, an evaluation of the existing clinical data 
should be conducted to justify such change. If the clinical data alone are inadequate to support 
the change in schedule, the factors discussed in section III.C (3.3) above should be considered. 
 
E. 	 Combination of Pharmaceuticals (3.5) 
 
Pharmaceuticals planned for use in combination should be well studied individually in 
toxicology evaluations. Data to support a rationale for the combination should be provided prior 
to starting the clinical study. In general, toxicology studies investigating the safety of 
combinations of pharmaceuticals intended to treat patients with advanced cancer are not 
warranted.  If the human toxicity profile of the pharmaceuticals has been characterized, a 
nonclinical study evaluating the combination is not usually warranted.  For studies in which at 
least one of these compounds is in early stage development (i.e., the human toxicity profile has 
not been characterized), a pharmacology study to support the rationale for the combination 
should be provided.  This study should provide evidence of increased activity in the absence of a 
substantial increase in toxicity on the basis of limited safety endpoints, such as mortality, clinical 
signs, and body weight. Based on available information, a determination should be made 
whether or not a dedicated toxicology study of the combination is warranted. 
F.  Nonclinical Studies to Support Trials in Pediatric Populations (3.6) 
 
The general paradigm for investigating most anticancer pharmaceuticals in pediatric patients is 
first to define a relatively safe dose in adult populations and then to assess some fraction of that 
dose in initial pediatric clinical studies.  The recommendations for nonclinical testing outlined 
elsewhere in this document also apply for this population.  Studies in juvenile animals are not 
usually conducted in order to support inclusion of pediatric populations for the treatment of 
cancer. Conduct of studies in juvenile animals should be considered only when human safety 
data and previous animal studies are considered insufficient for a safety evaluation in the 
intended pediatric age group. 
 
 
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IV.  OTHER CONSIDERATIONS (4) 
 
A.  Conjugated Products (4.1) 
 
Conjugated products are pharmaceuticals covalently bound to carrier molecules, such as 
proteins, lipids, or sugars. The safety of the conjugated material is the primary concern.  The 
safety of the unconjugated material, including the linker used, can have a more limited 
evaluation. Stability of the conjugate in the test species and human plasma should be provided. 
A toxicokinetic evaluation should assess both the conjugated and the unconjugated compound 
after administration of the conjugated material.   
B.  Liposomal Products (4.2) 
 
A complete evaluation of the liposomal product is not warranted if the unencapsulated material 
has been well characterized. As appropriate, the safety assessment should include a 
toxicological evaluation of the liposomal product and a limited evaluation of the unencapsulated 
pharmaceutical and carrier (e.g., a single arm in a toxicology study).  The principle described 
here might also apply to other similar carriers.  A toxicokinetic evaluation should be conducted 
as appropriate. If possible, such an evaluation should assess both the liposomal product and the 
free compound after administration of the liposomal product. 
C.  Evaluation of Drug Metabolites (4.3) 
 
In some cases, metabolites that have been identified in humans have not been qualified in 
nonclinical studies. For these metabolites, a separate evaluation is generally not warranted for 
patients with advanced cancer. 
D.  Evaluation of Impurities (4.4) 
 
It is recognized that impurity standards have been based on a negligible risk, as discussed in ICH 
Q3A and Q3B. Exceeding the established limits for impurities identified in these ICH guidances 
could be appropriate for anticancer pharmaceuticals, and a justification should be provided in the 
marketing application.  The justification could include the disease being treated and the patient 
population, the nature of the parent pharmaceutical (pharmacologic properties, genotoxicity and 
carcinogenic potential, etc.), duration of treatment, and the impact of impurity reduction on 
manufacturing.  Further, the qualification assessment could include consideration of either the 
dose or concentration tested in nonclinical study relative to clinical levels.  For genotoxic 
impurities, several approaches have been used to set limits based on increase in lifetime risk of  
cancer. Such limits are not appropriate for pharmaceuticals intended to treat patients with 
advanced cancer, and justifications described above should be considered to set higher limits.  
Impurities that are also metabolites present in animal and/or human studies are generally 
considered qualified. 
 
 
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Table 1: Examples of Treatment Schedules for Anticancer Pharmaceuticals to Support 
Initial Clinical Trials  
 
Clinical Schedule  Examples of Nonclinical Treatment Schedule1,2,3,4 
Once every 3-4 weeks  Single dose 
Daily for 5 days every 3 weeks  Daily for 5 days 
Daily for 5-7 days, alternating  Daily for 5-7 days, alternating weeks (2-dose cycles) 
weeks 
Once a week for 3 weeks,  Once a week for 3 weeks 
1 week off 
Two or three times a week   Two or three times a week for 4 weeks 
Daily  Daily for 4 weeks 
Weekly  Once a week for 4-5 doses  
1 Table 1 describes the dosing phase. The timing of the toxicity assessment(s) in the nonclinical studies 

should  be scientifically justified based on the anticipated toxicity profile and the clinical schedule. For 

example, both a sacrifice shortly after the dosing phase to examine early toxicity and a later sacrifice to 
 
examine late onset  of toxicity should be considered.  

2 For further discussion  regarding  flexibility in the relationship of the clinical schedule and the nonclinical 
toxicity studies, see section III.C (3.3). 

3 The treatment schedules described in the table do  not specify recovery periods (see section II.D (2.4) and 

Note 1 regarding  recovery).
  
4 The treatment schedules described in this table should be  modified as appropriate for molecules with
  
extended pharmacodynamic effects, long half-lives or potential for anaphylactic reactions. In addition, the 

potential effects of immunogenicity should be considered (see ICH S6). 
 
 
 
V.  NOTES (5) 
 
1. For nonrodent studies, dose groups usually consist of at least 3 animals/sex/group, with an 
additional 2/sex/group for recovery, if appropriate (see section II.D (2.4)).  Both sexes should 
generally be used, or justification should be given for specific omissions. 
 
2. A common approach for many small molecules is to set a start dose at  1/10 the severely toxic 
dose in 10% of the animals (STD 10) in rodents.  If the nonrodent is the most appropriate 
species, then 1/6 the highest non-severely toxic dose (HNSTD) is considered an appropriate 
starting dose. The HNSTD is defined as the highest dose level that does not produce evidence of 
lethality, life-threatening toxicities or irreversible findings. 
 
 
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