Ritam Das, Technical Development Scientist 2, Genentech/ Roche
Ritam Das, Technical Development Scientist 2, Genentech/ Roche
Biography
Ritam Das is a scientist driven by the belief that the future of medicine lies in unlocking the full potential of RNA and gene therapies. With over six years of experience at the cutting edge of formulation science, he has helped shape delivery systems, like lipid nanoparticles and polymeric carriers, that bring these powerful therapeutics closer to patients. Currently at Poseida Therapeutics (acquired by Roche/Genentech), Ritam leads LNP process development for IND-enabling studies, translating complex science into scalable, clinic-ready solutions. His Ph.D. work at UMass Amherst, under Prof. Sankaran Thayumanavan, focused on antibody-directed delivery of mRNA and siRNA to tumor and immune cells, an effort that earned him multiple publications and recognition across the field. Beyond the lab, Ritam is a collaborative leader and mentor, committed to science that not only innovates but heals. He envisions a world where precision delivery enables cures once thought impossible, and he’s building platforms to make that vision real.
Interview
NanoSphere: Tell us a bit about yourself—your background, journey, and what led you to where you are today.
Ritam: Hi! I’m originally from India, where I began my academic journey studying chemistry at Ramakrishna Mission Vidyamandira in West Bengal. I then pursued my master’s at IIT Kharagpur, which is really where I first got exposed to research and started thinking seriously about a career in science.
Funny enough, doing a Ph.D. wasn’t always part of the plan—it happened through what I like to call a “comedy of errors.” But I landed in the Chemistry Ph.D. program at UMass Amherst, working in Prof. Sankaran Thayumanavan’s lab, and that turned out to be one of the best things that’s happened to me. The mentorship I received from my PI, lab mates, and collaborators has shaped the scientist I am today.
I started off doing organic synthesis, developing zwitterion-based lipids with tunable reactivity, and that work sparked my interest in lipid-based delivery for gene therapy. It was an exciting time to be in the field, right before lipid nanoparticles became central to RNA therapeutics with the COVID vaccines.
During my Ph.D., I also had the opportunity to intern at Eli Lilly, where I worked on polymeric nanocapsules for CNS delivery. That experience really opened my eyes to how science operates in an industry setting and solidified my interest in working in biotech.
After completing my Ph.D., I joined Poseida Therapeutics as a Process Development Scientist, which was another pivotal step. I gained hands-on experience in formulation scale-up, manufacturing, and tech transfer areas I hadn’t appreciated fully before. It gave me a broader understanding of how therapies go from the bench to the clinic.
Most recently, Poseida was acquired by Genentech/Roche, so I now find myself part of an incredible team within Genentech. It’s been a journey filled with learning, unexpected turns, and great mentors and I’m excited for what comes next.
NanoSphere: Given your work bridging preclinical formulations to GMP-compliant processes, how do you approach balancing innovation in nanoparticle design with the constraints of scalability and regulatory expectations? You’ve led DOE-driven optimization for LNP formulations at Poseida—what are some underappreciated parameters that significantly affect nanoparticle performance but often get overlooked in early-stage development?
Ritam: Taking a formulation from R&D scale through process development and into tech transfer has been one of the most rewarding experiences in my career so far. Leading DOE-driven optimization for LNP formulations at Poseida gave me a deep appreciation for the complexities involved in making a formulation scalable and robust enough for clinical manufacturing.
One of the biggest lessons I’ve learned is how much more rigor and documentation are required as you move beyond early development. Even small changes like tweaks in buffer composition or mixing parameters need to be thoroughly documented and justified. Alongside that, constraints such as short-term material stability, batch volume limits, and the capabilities of available instrumentation play a big role in shaping the process. Coordinating logistics and ensuring alignment between teams is also critical to minimize variability during scale-up and tech transfer.
While I’m not directly involved in GMP manufacturing, being part of process development and tech transfer has taught me the importance of building a strong foundation early on. Something that’s often overlooked at the R&D stage but becomes crucial during tech transfer is the development and validation of analytical methods and biological assays. Having robust analytics is essential to characterize the final drug product, ensure quality, and satisfy regulatory requirements. In fact, these tools can be even more important than the formulation itself when it comes to successful translation.
Ultimately, I believe balancing innovation with scalability means designing formulations and processes with the full development pathway in mind—anticipating constraints, emphasizing reproducibility, and aligning cross-functionally to facilitate smooth tech transfer and beyond.
NanoSphere: In your experience scaling up lipid nanoparticles for IND-enabling studies, what are some of the biggest technical or operational surprises that arise when transitioning from lab-scale to CDMO tech transfer? You’ve worked with polymer-based systems and LNPs—can you share insights into when a polymeric carrier might outperform an LNP in terms of stability or targeting, especially in the context of nucleic acid therapeutics?
Ritam: In my experience scaling up LNPs for IND-enabling studies at Poseida, one of the biggest technical surprises was how dramatically small differences in process conditions could impact final product quality. For example, during microfluidic mixing, we found that even slight shifts in total flow rate or flow rate ratio could alter particle size, polydispersity, and encapsulation efficiency in ways that weren’t apparent at bench scale. These effects became much more pronounced when we moved to larger-scale mixers and CDMO platforms. Operationally, the transition also highlighted how important raw material consistency is, especially with ionizable lipids and PEG-lipids, where lot-to-lot variability can subtly shift formulation behavior.
Ritam: In my experience scaling up LNPs for IND-enabling studies at Poseida, one of the biggest technical surprises was how dramatically small differences in process conditions could impact final product quality. For example, during microfluidic mixing, we found that even slight shifts in total flow rate or flow rate ratio could alter particle size, polydispersity, and encapsulation efficiency in ways that weren’t apparent at bench scale. These effects became much more pronounced when we moved to larger-scale mixers and CDMO platforms. Operationally, the transition also highlighted how important raw material consistency is, especially with ionizable lipids and PEG-lipids, where lot-to-lot variability can subtly shift formulation behavior.
Another challenge I encountered was with TFF and fill-finish processes. Parameters like diafiltration volume, buffer exchange rate, and hold times—often taken for granted in small-scale workflows—needed careful optimization to preserve particle integrity and meet stability specs. These weren’t just technical adjustments; they required deep cross-functional coordination across formulation, analytical, and quality teams, something I had to navigate closely during tech transfer.
In terms of delivery systems, my Ph.D. work at UMass Amherst focuses on polymer-lipid hybrid nanoparticles for siRNA and mRNA delivery, especially antibody-conjugated systems. One thing that stood out to me was how polymeric carriers offered more design flexibility, particularly for targeted delivery and controlled degradation. For instance, we designed dual-targeting nanoparticles (and found that the modular nature of polymeric backbones allowed us to tune surface presentation and degradation profiles more precisely than LNPs.
So, while LNPs are ideal for applications requiring scalability and systemic delivery, I’ve seen firsthand how polymeric systems can offer advantages in stability, targeting specificity, and triggered release, particularly for niche applications
NanoSphere: If there’s one key message or insight you’d like to share with readers about the future of nanomedicine, what would it be?
Ritam: At this point, I’m genuinely convinced that the future of nanomedicine is incredibly promising. What we’re seeing now in the field feels like just the tip of the iceberg. While nanotechnology has long been explored in academia, it’s exciting to witness its rapid traction and real-world impact in the biopharma industry over the last few years. That said, there are still important challenges ahead—particularly in striking the right balance between efficacy and safety. As we move toward treating more complex and heterogeneous diseases, it’s clear that success will require a true integration of both chemistry and biology. Ultimately, while innovative ideas are essential, it’s execution, how well we translate those ideas into reliable, scalable, and clinically viable solutions that will determine which technologies truly make it to the clinic.
Ritam: At this point, I’m genuinely convinced that the future of nanomedicine is incredibly promising. What we’re seeing now in the field feels like just the tip of the iceberg. While nanotechnology has long been explored in academia, it’s exciting to witness its rapid traction and real-world impact in the biopharma industry over the last few years. That said, there are still important challenges ahead—particularly in striking the right balance between efficacy and safety. As we move toward treating more complex and heterogeneous diseases, it’s clear that success will require a true integration of both chemistry and biology. Ultimately, while innovative ideas are essential, it’s execution, how well we translate those ideas into reliable, scalable, and clinically viable solutions that will determine which technologies truly make it to the clinic.