1. Using Q-learning Method in Identify Optimal Treatment Regime
Haocheng Li Vincent Shen Hao Xu Sylvia Hu

2. Background
Lung cancer is one of the most commonly diagnosed cancers and is a leading cause of cancer death worldwide
Non-small-cell lung cancer (NSCLC) is the most common type of lung cancer
Bevacizumab (Bev), sold under the trade name Avastin®, is a recombinant, humanized monoclonal antibody, which acts against vascular endothelial growth factor (VEGF)
When used in combination with chemotherapy as first-line treatment in patients with advanced NSCLC, bevacizumab significantly improves patient’s survival outcomes

3. Line of Therapy in Cancer Treatment
Sequential systemic therapies are commonly used for advanced cancer
Death
Advanced
NSCLC
Diagnosed
Start Treatment
for 1L Therapy
Disease Progression/ Toxicity
Treatment Change
to 2L Therapy
to 3L Therapy

4. Induction and Post-Induction Phase
First-line treatment could also be divided into induction phase (IP) and maintenance phase (or post-induction phase, post-IP )
Post-IP is a continuation of one or more drugs used in the induction regimen ……
Advanced
NSCLC
Diagnosed
Start Treatment
for IP in First-line
Disease Progression/ Toxicity
Treatment Change
to post-IP in First-line
to 2L Therapy
No progression
or Death

5. ARIES Observational Cohort Study
Avastin® Registry—Investigation of Effectiveness and Safety (ARIES) observational cohort study
Patient cohort had bevacizumab (Bev) and chemotherapy as IP therapy
Patient can be Bev exposure or non-Bev exposure as Post-IP therapy
After disease progression, patient can be Bev exposure or non-Bev exposure as second-line therapy
Potential confounding factors such as age, gender, smoking status, diabetes status, alk phosphatase level and albumin, are recorded
Overall survival is set to be primary outcome in this study
Later line of therapies depending on the response to the previous treatment and patient status

6. Patient flowchart and analysis cohorts
post-IP (n=1050)
post-IP: Bev exposure (n=502)
post-IP: Non-Bev exposure (n=548)
Death or Censoring (n=102)
Death or Censoring (n=164)
Progression
Progression
2L: Bev exposure (n=118)
2L: Non-Bev exposure (n=282)
2L: Bev exposure (n=75)
2L: Non-Bev exposure (n=309)

7. Methods
Proposed methods
G-estimation
Dynamic weighted OLS
Q-learning

8. Future Extension
With the development of electronic medical record, the treatment history of cancer patients can be recorded in convenience.
Instead of Bev exposure vs Non-Bev exposure selection, multiple treatment selections are available such as chemotherapy, immunotherapy and targeted therapy
Instead of two treatment lines, patients may also get third, fourth or later lines in real world practice
High dimensional biomarker information can be utilized for dynamic treatment decision

9. Doing now what patients need next