Here’s a disease most people have never heard of that affects tens of millions of patients: anemia of inflammation.

Chronic kidney disease patients get it. Lupus and rheumatoid arthritis patients get it. Cancer patients get it.

Their bodies produce too much hepcidin, iron gets locked away from red blood cell production, and the immune dysregulation on top of it kills erythropoiesis. You end up tired, pale, and sometimes transfusion-dependent, and the only real tools are ESAs and IV iron, both of which come with serious baggage.

Nobody has cracked this problem.

Protagonist and Takeda are pushing rusfertide, a hepcidin mimetic, but for polycythemia vera, which is basically the opposite problem. Everyone else is either chasing single-mechanism hepcidin antagonists or recycling iron-regulatory approaches that have been tried before.

Well Ferrosa Therapeutics AG just raised a $3.5 million seed round led by Forty51 Ventures to try something different.

They’re building a bispecific antibody that hits two mechanisms at once.

From what I can tell, they haven’t publicly disclosed the targets, but the positioning is clear: dual-mechanism, first-in-class, aimed at the root causes of iron dysregulation and impaired erythropoiesis simultaneously.

In anemia of inflammation, it’s a genuinely new idea.

Now, $3.5 million isn’t going to get anyone to the clinic. To be honest, it probably won’t even finish antibody engineering and in vivo proof-of-concept.

That’s what this round is earmarked for, which tells you Ferrosa is pre-lead optimization.

But I think this still pretty interesting – check out their setup.

Based in Basel, which is CKD country. Backed by Forty51, which has a track record with Swiss and German biotechs. And the indication list is deliberately broad: chronic kidney disease, autoimmune disorders, and cancer-associated anemia.

Any one of those is a billion-dollar market. All three together is a fundamentally different company.

Ferrosa’s bet is that the bispecific approach is the right tool for a disease where single-mechanism drugs keep failing:

hit the inflammatory driver and the iron-handling defect in one molecule. Restore enough red blood cell production to actually change outcomes instead of just propping them up with ESAs.

We’ll see.

Pre-IND bispecific antibody programs have a long road.

But the seed is priced to survive to the next round, and the Forty51 lead suggests at least one fund has seen the data behind closed doors.

Keep this one on the list.

Not because $3.5 million moves markets, but because if the antibody works, anemia of inflammation stops being the condition nobody knows how to treat.