Parkinson’s disease cell therapy-focused Aspen Neuroscience and bispecific biotech Bambusa Therapeutics are the latest drug developers to eye up a public listing.
Both companies disclosed their IPO ambitions in Securities and Exchange Commission filings on Friday, although they have yet to set out how many shares they are likely to offer or at what price.
Aspen’s move comes off the back of promising phase 1/2a data for its Parkinson’s asset. The autologous therapy, called sasineprocel, is designed to turn skin cells from patients into stem cells that are then prompted to become new neurons to be implanted into the brain.
According to the March readout, patients saw marked improvements in measures of symptom control, motor function and quality of life one year after receiving either a low or high dose of sasineprocel.
At the time, Aspen CEO Damien McDevitt, Ph.D., told Fierce that the fact that some patients in the trial were able to reduce the amount of levodopa they were taking to manage symptoms was a good indicator that the transplanted neurons are producing dopamine.
Motor symptoms in Parkinson’s are caused by the progressive loss of dopaminergic neurons, so patients typically take levodopa to supplement their levels of the neurotransmitter.
Top of the list of spending priorities for the IPO proceeds will be continuing that phase 1/2a study, according to Friday’s filing. The company will also need cash to kick off a phase 3 trial of sasineprocel in Parkinson’s, which the biotech expects to launch before the earlier study has completed.
Should the phase 3 succeed and sasineprocel gain approval, McDevitt has previously told Fierce that he thinks Aspen can commercialize the therapy itself and use it as a springboard to take the biotech’s stem cell platform to the next level.
The company is also planning to spend some of the IPO proceeds on its autologous microglia cell replacement therapies. These will initially be aimed at a group of rare, genetically defined neurological disorders called leukodystrophies with a target of beginning human trials in the second half of 2027.
The San Diego-based biotech launched in 2019 with $6.5 million and a mission to develop the first autologous cell therapies for Parkinson's. The company’s approach has its origins in the lab of Aspen’s co-founder Jeanne Loring, Ph.D., the founding director of the Center for Regenerative Medicine at The Scripps Research Institute.
By 2020, Aspen had raised a $70 million series A—whose investors included Open AI CEO Sam Altman—followed by a $147.5 million series B in 2022, and a $115 million series C in November 2025. That most recent round saw Gilead Sciences' cell therapy unit Kite Pharma pitch in.
As of the end of June, the company numbered 120 full-time employees and had $72.4 million in the bank.
Bambusa also banks on an IPO
Bambusa is a slightly fresher-faced startup, having only formed in May 2024. The Boston-based biotech went on to raise a $15 million seed financing later that year, followed by a $90 million series A in 2025.
The company is led by founder and CEO Shanshan Xu, M.D., Ph.D., who previously held leadership roles at BioNTech and Berenberg Capital Markets. Xu oversees a workforce of 30 full-time employees and Bambusa had $71.5 million to hand by the end of June, according to Friday's filing.
The company’s top spending priority for the IPO cash would be BBT001, including taking the asset into a phase 2b study for atopic dermatitis (AD). BBT001 is a next-generation, long-acting bispecific antibody targeting both interleukin-4 receptor alpha (IL-4Rα) and IL-31.
BBT001 is already undergoing a global phase 1 trial for AD, as well as a phase 2 study in chronic spontaneous urticaria in China.
In July, the company touted “potentially transformative” preliminary data of 17 patients from the phase 1 study that showed that 82% of those who received BBT001 achieved a more than 50% improvement in eczema area and severity by Week 6 when adjusted for placebo.
Funds will also be needed to progress BBT002, a long-acting bispecific antibody targeting IL-4/13 and IL-5. Bambusa has already taken BBT002 into a global phase 1 study for chronic obstructive pulmonary disease (COPD), as well as a phase 1/2a and a phase 2a trial in China for COPD and chronic rhinosinusitis with nasal polyps, respectively.
The IPO interest from both Aspen and Bambusa came the same day that TRex Bio and Retension Pharmaceuticals joined the Nasdaq with IPOs of $116.7 million and $45 million, respectively. So far, 2026 has already seen record-breaking biotech listings from the likes of Kailera Therapeutics and Parabilis Medicines.
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