1. Provided written informed consent
2. Has reached the age of majority in the country of treatment (i.e. ≥ 18 years in
Australia; ≥ 21 years in Singapore)
3. Histological or cytological documented NSCLC
4. Metastatic NSCLC, not amenable to curative surgery or curative radiotherapy
5. Brain metastases that meet the following criteria;
1. ≤ 10 lesion/s visible and measurable on protocol screening MRI;
- At least one brain metastases able to be treated with SRS
- Definite but small brain metastases not for SRS treatment due to size, as
per physician discretion, are included in the total
- Equivocal small lesions are not included in the total
2. No single brain metastasis exceeding 30mm longest diameter
3. Total brain metastasis volume ≤ 15cc;
- Total brain metastases volume on protocol screening MRI should be using the
formula (4/3) x (3.14159265359) x (1/2 x size lesion in centimetre)3. Table 1:
Brain metastases volume estimates provides an estimate of the volume of brain
metastases based on the size of the lesion
4. Diagnosed de novo (i.e. at the same time with a new diagnosis of NSCLC) or
developed as a new site of progression while on first line EGFR TKI
NOTE: Surgery as part of local practice for the management of brain metastasis is
allowed but must be completed between 2 to 4 weeks prior to randomisation. Patients
must still fulfil criteria 5a, 5b and 5d pre-surgery, and have at least one target
lesion post-surgery to be eligible for the study. Lesions that are partially or
completely resected should not be used as a target lesion for MRI assessment.
6. Documented EGFR mutation;
1. Patients who developed brain metastases as a site of disease progression while on
first line EGFR TKIs must have T790M mutation.
2. Documented EGFR mutation (at any time since the initial diagnosis of NSCLC) known
to be sensitive to Osimertinib - These include exon 19 del; L858R (exon 21);
G719X (exon 18); L861G (exon 21); S768I (exon 20) and T790M (exon 20) NOTE:
Mutation analysis is to be done as per local practice. Please see section 7.1.1
for the recommended clinical practice for analysis.
7. Are one of the following cohorts:
1. First-line metastatic cancer: All newly diagnosed participants with documented
sensitising EGFR mutation (criterion 6) and intracranial metastasis (criterion
5), with/without extracranial disease
2. Second-line metastatic cancer (T790M+): Participants who progressed after
first-line 1st or 2nd generation EGFR TKI therapy with intracranial progression
(criterion 5), with/without extracranial disease and have documented T790M
3. Second-line metastatic cancer (T790M-): Participants with no T790M mutation who
progressed after first-line 1st or 2nd generation EGFR TKI therapy with
intracranial progression (criterion 5) but has no extracranial disease
4. Second-line metastatic cancer (T790M-): Participants with no T790M mutation who
progressed after first-line 1st or 2nd generation EGFR TKI therapy with
intracranial progression (criterion 5) but has stable extracranial disease
8. Karnofsky performance status 60-100 (ECOG performance status ≤2) with no deterioration
over the previous 2 weeks and a minimum life expectancy of 12 weeks
9. Female patients who;
1. are willing to use adequate contraceptive measures until 6 weeks after the final
dose of study treatment
2. are not breast feeding
3. have a negative pregnancy test prior to the start of dosing if of child bearing
potential or have evidence of non-child bearing potential by fulfilling one of
the following criteria at screening:
i. Post-menopausal defined as aged more than 50 years and amenorrheic for at least 12
months following cessation of all exogenous hormonal treatments ii. Women under 50
years old would be considered postmenopausal if they have been amenorrheic for 12
months or more following cessation of exogenous hormonal treatments and with
Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH) levels in the
post-menopausal range for the institution iii. Documentation of irreversible surgical
sterilization by hysterectomy, bilateral oophorectomy or bilateral salpingectomy but
not tubal ligation
10. Male patients who are willing to use barrier contraception (i.e. condoms) until 4
months after the final dose of study treatment
1. Treatment with any of the following:
1. Prior systemic therapy for patients with newly diagnosed metastatic NSCLC and
brain metastases de novo.
NOTE: Prior adjuvant chemotherapy or chemotherapy used as radio sensitisation
followed by maintenance immunotherapy for non-resectable early stage NSCLC are
allowed if such treatments were more than 6 months ago.
2. Prior whole brain radiotherapy (WBRT)
3. Radiologically progressive brain metastasis that underwent prior SRS (second line
4. Previous treatment with Osimertinib or a 3rd generation EGFR TKI.
5. Previous treatment with checkpoint inhibitors immunotherapy for metastatic NSCLC.
6. Major surgery within 4 weeks of randomisation (excluding placement of vascular
access and surgery as part of local practice for the management of brain
metastases, as outlined in inclusion criterion 5).
7. Radiotherapy treatment to more than 30% of the bone marrow or with a wide field
of radiation within 4 weeks of randomisation.
8. Medications or herbal supplements known to be potent inducers of CYP3A4 and are
unable to stop use within the recommended wash out period prior to receiving the
first dose of Osimertinib, see Table 7: Medications to avoid and withdrawal
periods and Table 8 NOTE: All patients must try to avoid concomitant use of any
medications, herbal supplements and/or ingestion of foods with known inducer
effects on CYP3A4
9. An investigational drug within five half-lives of the compound or 3 months,
whichever is greater.
10. Any other cytotoxic chemotherapy, investigational agents or other anticancer
drugs from a previous treatment regimen or clinical study within 14 days of
2. Any unresolved toxicities from prior therapy greater than CTCAE grade 1 (with the
exception of alopecia grade 2) at the time of starting study treatment.
3. Spinal cord compression unless asymptomatic and stable.
4. Leptomeningeal disease.
5. Moderate or severe symptomatic brain metastases defined as per Radiation Therapy
Oncology Group acute morbidity grade 3 to 4.
- Grade 3 refers to neurological findings requiring hospitalisation for initial
- Grade 4 refers to serious neurological impairment including paralysis, coma or
seizures more than three times per week despite medication and requires
6. Brain metastases in the brainstem.
7. Any evidence of severe or uncontrolled systemic diseases, including uncontrolled
hypertension and active bleeding diatheses, which in the investigator's opinion makes
it undesirable for the patient to participate in the trial or which would jeopardize
compliance with the protocol, or active infection including hepatitis B, hepatitis C
and human immunodeficiency virus (HIV). Screening for chronic conditions is not
8. Refractory nausea and vomiting, chronic gastrointestinal diseases, inability to
swallow the formulated product or previous significant bowel resection that would
preclude adequate absorption of Osimertinib.
9. Any of the following cardiac criteria:
1. Resting corrected QT interval (QTc) > 470 msec, obtained from an
2. Any clinically important abnormalities in rhythm, conduction or morphology of
resting ECG e.g. complete left bundle branch block, third degree heart block or
second degree heart block.
3. Any factors that increase the risk of QTc prolongation or risk of arrhythmic
events such as heart failure, electrolyte abnormalities (including: Serum/plasma
potassium < LLN; Serum/plasma magnesium < LLN; Serum/plasma calcium < LLN),
congenital long QT syndrome, family history of long QT syndrome or unexplained
sudden death under 40 years of age in first degree relatives or any concomitant
medication known to prolong the QT interval.
10. Patients with congenital long QT syndrome (CLQTS)
11. Past medical history of Interstitial Lung Disease (ILD), drug-induced ILD, radiation
pneumonitis which required steroid treatment, or any evidence of clinically active
interstitial lung disease.
12. Inadequate bone marrow reserve or organ function as demonstrated by any of the
following laboratory values:
1. Absolute neutrophil count < 1.5 X 109/L
2. Platelet count < 100 X 109/L
3. Haemoglobin < 90 g/L
4. Alanine aminotransferase (ALT) > 2.5 times the upper limit of normal (ULN) if no
demonstrable liver metastases or > 5 times ULN in the presence of liver
5. Aspartate aminotransferase (AST) > 2.5 times ULN if no demonstrable liver
metastases or > 5 times ULN in the presence of liver metastases.
6. Total bilirubin > 1.5 times ULN if no liver metastases or > 3 times ULN in the
presence of documented Gilbert's Syndrome (unconjugated hyperbilirubinemia) or
7. Creatinine > 1.5 times ULN concurrent with creatinine clearance < 50ml/min
(measured or calculated by Cockcroft and Gault equation); confirmation of
creatinine clearance is only required when creatinine is > 1.5 times ULN.
13. History of hypersensitivity of drugs with a similar chemical structure or class to
Osimertinib or any excipients of these agents.
14. Involvement in the planning and conduct of the study
15. Judgement by the investigator that the patient should not participate in the study if
the patient is unlikely to comply with study procedures, restrictions and