Vintafolide showed promising results in a phase 2 study for treating non-small cell lung cancer (NSCLC). It met its primary endpoint of clinical benefit and was well tolerated. Patients with 100% folate receptor positive tumors had significantly improved progression-free survival of 7.2 months compared to 1.7 months for patients with 10-90% folate receptor positive tumors. Overall survival was also significantly improved at 10.9 months for fully folate receptor positive patients compared to 3.4 months for partially positive patients. These results suggest vintafolide has positive activity as a single agent, especially for fully folate receptor positive NSCLC patients who have failed multiple prior therapies.

1. Vintafolide in NSCLC - Phase 2 Study Design & Results
• Leading cause of cancer death
Unmet need • Overall Survival <6 months
• 80% of patients folate receptor positive
• Eligibility:
Vintafolide – Failed >2 prior therapies
Evaluated in – Folate receptor positive
Advanced Patients • Advanced disease:
– 42% failed ≥4 prior therapies
– Bulky disease - median tumor length of 7.9 cm
• Met primary endpoint of clinical benefit
Positive Results • Well tolerated
• Significant improvement in OS in FR(100%) patients
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2. Positive Signal - Single Agent Vintafolide in FR(100%) NSCLC
Progression Free Survival Overall Survival
Probability of Survival
Probability of Survival
FR(100%)
FR(100%)
FR(10-90%)
FR(10-90%)
Weeks from First Administration of Vintafolide Weeks from First Administration of Vintafolide
Progression Free Survival FR(100%) FR(10%-90%) Overall Survival FR(100%) FR(10-90%)
N=14 N=14 N=14 N=14
Median PFS months. 7.2 1.7 Median OS months. 10.9 3.4
Hazard Ratio (2-sided p-value) 0.326 p=0.028 Hazard Ratio (2-sided p-value) 0.539 p=0.202
Note: FR(x%) – x refers to percent of target lesions determined to be positive for the folate receptor by the etarfolatide scan. 25

3. Promising Phase 2 Vintafolide Results in NSCLC vs.
Standard Regimens
Regimens Response Rate PFS (months) Survival (months)
First-line
Navelbine/Cisplatin 19% - 9.2
Taxol/Cisplatin 25% 4.3 (TTP) 9.3
Gem/Cisplatin 26% 5.2 (TTP) 9.0
Taxotere/Cisplatin 32% 4.9 (TTP) 10.9
Taxol/Carbo/Avastina 35% 6.2 12.3
Gem/Cisplatin/Avastina 34% 6.7 -
First-line with maintenance
Alimta post platinum doublets - 4.0 13.4
Alimta post Alimta/platinum - 4.1 Not yet matured
Tarceva post platinum doublets - 2.8 12.0
Second and third-line
Taxotere – second-line 6% 1.9b ;2.8c 5.7b ;7.5c
Iressa – third-line 11% - -
Tarceva – second and third-line 9% 2.3 6.7
Vintafolide FR(100%) – Median 3rd line 7% 7.2 10.9
a Non-squamous NSCLC; b against BSC; c against Navelbine/Iphosphamide 26

4. TARGET trial design – Vintafolide in 2nd line NSCLC
Preclinical studies support
Phase 2b Design
combining with Docetaxel
2nd Line NSCLC
1600
Tumor Volume (mm3)
1400
1200 Etarfolatide
Folate Receptor
1000 Scan
800
KB Control
600 FR(100%)
Vintafolide
only
400 Docetaxel
200 Vintafolide + Docetaxel 1:1:1
Randomization
0
7 14 21 28 35 42 49 56
PTI (days) Vintafolide
Vintafolide Docetaxel
/Docetaxel
(n=60) (n=60)
(n=60)
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5. Promising Vintafolide results compared to standard
regimens in 2nd and 3rd line NSCLC
Regimens Response Rate PFS (months) Survival (months)
Taxotere
6% 1.9a ;2.8b 5.7a ;7.5b
2nd line
Alimta vs. Taxotere
9% vs. 8% 2.9 vs. 2.9 8.3 vs. 7.9
2nd line
Tarceva vs. placebo
9% vs. 1% 2.3 vs. 1.8 6.7 vs. 4.7
2nd & 3rd line
EC145 FR(100%)
7% 7.2 10.9
70% ≥3 prior Tx
a TTPD against Navelbine/Iphosphamide; bTTPD against BSC
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