With New Results, FibroGen’s Anemia Pill Inches Closer to FDA Review

Xconomy San Francisco — 

There was a new development today in the high-stakes race to use pills, not injectable biologic drugs, to treat anemia. San Francisco, CA-based FibroGen and partners AstraZeneca and Astellas Pharma have reported that their experimental drug, roxadustat, has succeeded in five more Phase 3 trials, which bolster its chances of approvals in the U.S. and Europe—if it proves safe when a key analysis is done next year.

In two separate statements, AstraZeneca (NYSE: AZN), FibroGen (NASDAQ: FGEN), and Astellas said roxadustat met its main goal in five studies known as Olympus, Rockies, Andes, Himalayas, and Sierras.

In one statement, AstraZeneca said that roxadustat led to a statistically significant boost in average hemoglobin levels for anemia patients with failing kidneys after between 28 and 52 weeks of treatment, compared to either a placebo (in the Olympus study) or a standard of care biologic (Rockies).

In Olympus, 2,781 patients with anemia and later-stage chronic kidney disease who weren’t on dialysis got either roxadustat or a placebo. In Rockies, 2,133 patients with anemia and CKD who are on dialysis got either roxadustat or epoetin alfa (Epogen), the blockbuster Amgen (NASDAQ: AMGN) biologic drug. AstraZeneca didn’t provide additional details.

In a second statement, FibroGen and Astellas said the drug met all of its main goals in Andes, Himalayas, and Sierras, which also tested roxadustat in patients with failing kidneys who either are or aren’t on dialysis. But they provided a few more details.

In Andes, for instance, 86 percent of those on roxadustat were deemed to respond within 24 weeks—meaning their hemoglobin levels were boosted to 11 g/dL of blood and by at least 1 g/dL—compared to 6.6 percent of placebo patients. Roxadustat also reduced the risk of needing blood transfusions or other rescue therapies within the first year of treatment.

In Himalayas, patients on roxadustat saw their hemoglobin levels spike by an average of 2.57 g/dL after between 28 and 52 weeks of treatment, compared to an average 2.36 g/dL boost for patients on epoetin alfa. The FibroGen drug also appears to have been superior to epoetin alfa in Sierras, which tested roxadustat against the biologic in patients who had been on epoetin alfa before starting the study.

The results are “better than expected” given roxadustat appears to have bested the Amgen drug in the slate of studies, not just matched it, Leerink Partners analyst Geoffrey Porges wrote in a research note. “These results speak quite positively on the efficacy component of roxadustat,” he wrote.

The news puts roxadustat closer to the regulatory finish line in the Western world. Roxadustat was just approved in China this week as a treatment for people with failing kidneys who are on dialysis; a similar nod in Japan could soon follow. But AstraZeneca, Astellas, and FibroGen’s ambitions are broader. The companies aim to file for approvals in the U.S. and Europe next year and stay ahead of similar, rival drugs from Akebia Therapeutics (NASDAQ: AKBA), GlaxoSmithKline (NYSE: GSK), and Bayer that are also either in late-stage testing or soon will be. The studies they reported on today are a key part of that strategy, as is a study, Alps, which produced positive results in September.

The companies are also pooling data from each of these studies into a large safety analysis, which is expected in the first half of 2019 and will include important information for regulators, payers, and clinicians.

FibroGen, AstraZeneca, Astellas, and its rivals are trying to upend the injectable anemia drugs, like epoetin alfa, that have generated billions in annual sales but carry risks of serious heart problems and don’t work for everyone. Roxadustat, Akebia’s vadadustat, GSK’s daprodustat, and Bayer’s molidustat are each pills that trick the body into thinking it’s in a low-oxygen environment, stimulating the production of more red blood cells. The hope is these drugs can be just as effective as epoetin alfa, but safer. The reward could be massive: sales of drugs like epoetin alfa, known as erythropoiesis-stimulating agents, or ESAs, generated $5 billion in sales in 2017 in the U.S. and Europe alone, according to Leerink analysts.

The results today show that the FibroGen drug is getting closer to proving that thesis. But it is still unknown whether the drug is safer than ESAs, which is particularly important for the companies to prove given a biosimilar version of epoetin alfa, from Pfizer (NYSE: PFE), has already been cleared by the FDA. The analysis expected next year pools the results of more than 9,000 patients and will show whether they’re more likely to have cardiovascular events—things like heart attacks and strokes—on roxadustat, ESA’s, or a placebo. The goal is for roxadustat to be “non-inferior” to a placebo or ESAs, and those results are critical for the drug to differentiate itself from its competitors, especially given the high risk of heart attacks with the current anemia treatments and in kidney disease patients themselves. In a recent research note, Porges predicted roxadustat “will be differentiated from current anemia medicines on cardiovascular safety.”

If roxadustat reaches the market, FibroGen would get royalties on sales of the drug in the U.S., Europe, and Japan. It splits profits with AstraZeneca in China.

AstraZeneca shares ticked up 2 percent in pre-market trading. FibroGen shares climbed about 5 percent.

Here’s more on roxadustat and the other companies developing anemia pills.

Corie Lok contributed to this report.