Fruquintinib differentiated VEGFR inhibition
Fruquintinib’s most advanced indications are in CRC (third-line) and NSCLC (third-line) in China, and data from the pivotal FRESCO Phase III in CRC will be presented at ASCO on 5 June. The drug is an oral small molecule that is a highly selective VEGFR1, VEGFR2 and VEGFR3 inhibitor (preclinical trials demonstrated fewer off-target toxicities, enabling higher drug exposure leading to 24 hours/day VEGFR receptor inhibition). First-generation VEGFR inhibitors such as Roche’s Avastin (monoclonal antibody administered intravenously) revolutionised the treatment of cancer by targeting the growth of blood vasculature that is essential for tumour growth (anti-angiogenesis). Oral, small molecule VEGFR inhibitors Nexavar (Bayer) and Sutent (Pfizer) are approved for use in some cancers (Nexavar in HCC and RCC, Sutent in GIST, RCC, and PNET). This highlights the unmet need for an oral anti-angiogenesis agent with a demonstrable impact on progression-free survival (PFS) in cancers such as NSCLC, CRC and breast cancer.
What differentiates fruquintinib from Nexavar and Sutent is its potent anti-VEGFR3 inhibition; the others inhibit VEGFR1 and VEFR2 only (Exhibit 3). Potent VEGFR3 activity could have utility in breast and lung cancer. Avastin is not approved for use in breast cancer; FDA removed the breast cancer indication from its label in 2011 due to lack of efficacy in this indication (it failed to improve survival for patients with mBC). Furthermore, Lilly’s VEGFR inhibitor, Cyramza, failed to demonstrate efficacy in breast cancer. The scientific community hypothesises that both drugs have failed in this indication due to lack of lymph angiogenesis control. It is believed that drugs, such as fruquintinib that inhibit VEGFR3 activity could, by interfering with lymph angiogenesis, have utility in breast and lung cancer. Fruquintinib’s ability to cover VEGFR1, 2 and 3 equally well with low off-target toxicity and its low risk of drug to drug interactions make it a suitable candidate for combination studies, and it serves as a differentiation factor from existing anti-angiogenesis agents.
Exhibit 3: VEGFR inhibitors
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Source: Company presentations
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FRESCO CRC full data at ASCO 2017; China FDA submission mid-year
Following positive, top-line pivotal Phase III trial results for fruquintinib in third-line colorectal cancer, HCM and partner Lilly are preparing for a China NDA submission in mid-2017; this represents the first China-based oncology innovation to succeed at Phase III. The China-based FRESCO study evaluating 416 patients who had failed at least two prior chemotherapies in CRC demonstrated a clinically meaningful and statistically significant increase in both overall survival and progression-free survival compared to placebo. Furthermore, the trial did not identify any new or unexpected safety issues. The positive top-line Phase III dataset highlights the selectivity hypothesis of HCM’s TKI pipeline. The full data will be presented at ASCO on 5 June 2017. Depending on the strength of the NDA submission packages and speed of the China FDA, we anticipate fruquintinib launch in China in 2018. The speed of any approval in China is less clear than with the US FDA, but we expect it to take between six and 12 months. We assume the speed will depend on the quality of the data and a faster approval (nearer to six months) could be achieved if the Phase III data are compelling. In the US, a Phase I bridging study in Caucasian patients will initiate in 2017. This study should determine the dose required to take fruquintinib into US Phase II/II studies across its differing indications in preparation for a US NDA submission. Contingent on strong proof-of concept (POC) and Phase III results in fruquintinib clinical trials in China, Eli Lilly may exercise its option to co-develop fruquintinib globally under the terms of the 2013 licence agreement. We expect fruquintinib to enter US Phase II/III trials regardless of whether Lilly exercises its option.
FALUCA pivotal NSCLC programme top-line data expected in 2018
FALUCA, the Phase III registration trial in China, was initiated in December 2015 for third-line treatment in NSCLC, following a positive Phase II POC trial that reached the primary endpoint of PFS with no unexpected safety issues. FALUCA is a double-blind, placebo-controlled Phase III evaluating fruquintinib 5mg once-a-day plus best supportive care in four-week treatment cycles (three weeks on drug, one week off). 521 patients are being randomised to the fruquintinib group or the placebo group at a ratio of 2:1 across 45 centres in China. The primary endpoint is overall survival; secondary endpoints include progression-free survival, objective response rate, disease control rate and duration of response; top-line data are expected in mid-2018; trial enrolment is estimated to complete in Q317 and database close is anticipated by mid-2018. Further trials evaluating fruquintinib in NSCLC are planned for 2017/18, likely in combination with other targeted therapies, eg using two oral TKIs to target EGFR and VEGFR simultaneously. Notably, at the R&D day the company indicated that the Phase II safety run in combination with Iressa in first-line, advanced NSCLC patients is in progress and expected to complete by year end 2017; the Phase II/III trial will follow once the safe dose has been established.
Global development to focus on combination studies
At the American Association for Cancer Research (AACR) 2017 meeting, HCM presented data on fruquintinib in combinations with targeted therapies or immune checkpoint inhibitor in preclinical tumour models. While at a very early stage, HCM reported that the efficacy observed in these models suggested that simultaneous blockade of tumour angiogenesis and tumour cell signalling or immune evasion might be a promising approach in improving treatment outcomes. Fruquintinib’s low risk of drug-to-drug interactions due to lack of Cytochrome P450 (CYP450 family of isozymes responsible for the metabolism of several drugs within the body) inhibition/inducing is favourable for potential in combination treatment regimens, given that many drugs are metabolised through the cytochrome P450 enzyme pathway. To compete in the global anti-angiogenesis inhibition setting, clinical trials will focus on more proprietary combination studies (eg fruquintinib plus savolitinib in clear cell renal cell carcinoma, fruquintinib plus Iressa in first-line NSCLC, fruquintinib plus Taxol in second-line gastric cancer). The Phase II/III trial in second-line gastric cancer is evaluating the combination of fruquintinib to paclitaxel (Taxol) compared to paclitaxel alone. Approximately 540 patients are being randomised between the two groups and an interim analysis will take place after the first 100 patients are treated. HCM expects full enrolment by H219; we anticipate top-line data could be available early 2020.
Peak sales and China commercialisation opportunity
We forecast global peak sales for fruquintinib of $2.3bn across the potential CRC, NSCLC and gastric cancer indications. Exhibit 4 details our assumptions. We have delayed our international launch year assumptions for CRC, NSCLC and gastric to reflect the ongoing US bridging studies and the uncertainty of time frames of US Phase II/III trials related to Lilly’s international co-development optionality. Timelines to reach our peak sales assumptions have additionally been pushed back; all else being equal, we have increased our peak sales numbers slightly as a function of our expected 2% pa price increase from launch year.
Exhibit 4: Fruquintinib peak sales forecasts
Product |
Indication |
Launch year/ peak sales China |
Launch year/ peak sales ROW |
Assumptions |
Fruquintinib |
CRC |
2018/2024 $106.6m |
2021/2026 $654.4m |
Global new cases (1,477,000), China new cases (283,000). China penetration 1%, $2,500 per month, 12-month treatment duration. ROW penetration 0.8%, $5,000 per month, 12-month treatment duration. |
NSCLC |
2020/2025 $297.6m |
2021/2025 $721m |
Global new cases (1,690,000), China new cases (623,000), China penetration 1.5%, $2,500 per month, 12-month treatment duration. ROW penetration 1.0%, $5,000 per month, 12-month treatment duration. We assume mainly in third-line NSCLC, but some use in additional lines. |
Gastric cancer |
2019/2026 $141.7m |
2021/2026 $391.9m |
Global new cases (1,034,000), China new cases (454,000). China penetration 1%, $2,500 per month, 12-month treatment duration. ROW penetration 1%, $5,000 per month, 12-month treatment duration. |
Deal economics |
Deal economics: $86.5m in upfront and milestones from Lilly royalty rate 15-20% on China, 11% ROW. Majority of development costs, all commercial costs in China. |
Source: Edison Investment Research. Note: FX rate US$1.25/£.